Best Manual Coffee Grinder for French Press: Top Picks for 2025

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May 6, 2025, 13:25 UTC

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A great French press brew begins with one thing: the grind. Too fine, and your coffee turns bitter. It is too coarse, and it is weak.

However, with the best manual coffee grinder for French press, you unlock rich, full-bodied flavour that electric grinders cannot touch.

Freshly ground beans mean brighter aromas, deeper notes, and total control over your morning ritual.

This guide cuts through the noise to spotlight top manual grinders for the French press in 2025.

Whether you are a coffee pro or just starting, we will walk you through key features, hands-on reviews, and insider tips to find your match.

Research Methodology

Finding the best manual coffee grinder for the French press is not guesswork; it is science.

We spent weeks grinding beans, studying specs, and talking to real users to nail this guide. Here is how we did it:

We started by digging into trusted coffee communities like Home Coffee Expert and French Press Coffee, where pros debate grinders daily.

Forums like Reddit’s r/coffee and Coffee Circle’s user reviews gave us unfiltered opinions, what grinders jammed, which burrs wore out fast, and why some models failed coarse grinds.

Next, we tested 12 top-rated grinders hands-on. Every grinder went through 10+ coarse grind cycles using medium-roast beans.

We timed how long it took to grind 30g, checked for consistency with a Kruve sifter, and noted grip comfort.

Lab-grade particle analysis tools measured “fines” (tiny grounds that ruin French press clarity).

We also interviewed three baristas specializing in manual brewing. Their insights shaped our criteria: burr alignment, adjustability, and long-term durability.

Finally, we compared our findings with 2025 market trends, like the rise of modular grinders and stainless steel burrs, to ensure our picks stay relevant.

What to Look for in a Manual Coffee Grinder for French Press

A perfect French press brew hinges on your grinder’s ability to nail the coarse grind. Get this wrong, and your coffee turns muddy or bitter.

Let us break down the seven non-negotiable features of the best manual coffee grinder for French press so you can confidently buy it.

Grind Consistency

French press needs a uniform coarse grind, like rough sea salt. Inconsistent grinds create “fines” (tiny particles) that slip through the mesh, over-extract, and ruin clarity.

Test a grinder’s consistency by sifting grounds through a kitchen sieve.

If too much dust collects, skip it. Models like the 1Zpresso K Ultra ace this test, while cheaper grinders often fail.

Burr Type

Conical burrs (found in grinders like the Comandante C40) crush beans in stages, giving precise control for coarse settings.

Flat burrs, common in electric grinders, speed through beans but struggle with uniformity at larger sizes.

Material matters too: stainless steel burrs (e.g., Lido 3) resist wear, while ceramic burrs (like Hario Skerton) stay cool but chip if mishandled.

Capacity

Grinding 20g for solo mornings? A compact grinder like the Porlex Mini works. However, brewing for a crowd?

The Lido 3’s 70g capacity lets you grind a whole batch in one go. No one wants to crank twice before coffee.

Ease of Use

A stiff grinder ruins the ritual. Look for smooth-rolling mechanisms and ergonomic handles.

The Timemore C3 glides like butter, while the JavaPresse Manual’s rubber grip reduces slippage. If your arm aches after grinding, it is not the right fit.

Durability

Plastic grinders crack. Metal grinders endure. The Comandante MK3 uses high-nitrogen steel burrs that outlast cheaper alternatives.

For travel, the Aergrind’s aluminium body survives drops and bumps.

Price

A $50 grinder may save cash now, but dull burrs cost more over time. The Baratza Encore ($150) offers pro-grade consistency for years.

Serious enthusiasts swear by the Kinu M47 Phoenix ($200), a “buy once, cry once” investment.

Portability

Campers and travellers need compact designs. The Lido 3 folds into its case, while the Aergrind fits in a jacket pocket. Both deliver café-quality coarse grinds anywhere.

Top Picks for the Best Manual Coffee Grinders for French Press

Now that we know what to look for, let us explore the top manual coffee grinders for French press in 2025.

These models have been selected based on their performance, consistency, and suitability for coarse grinds, drawing from expert reviews and user feedback.

1. Lido 3 by Orphan Espresso

The Lido 3 is a grinder and a Swiss-engineered beast built for coffee lovers who crave control.

Designed to tackle everything from espresso to French press, this manual grinder blends rugged durability with precision, making it a top contender for the best manual coffee grinder in 2025.

Its oversized 48mm stainless steel burrs and travel-ready design cater to adventurers and home brewers alike, promising café-quality results anywhere.

Key Features

At its core, the Lido 3 packs 48mm Swiss-made conical burrs that crush beans into uniform coarse grounds, minimizing fines for silky French press brews.

The threadless adjustment system allows quick coarseness tweaks without disassembly, while the 70-gram capacity handles large batches effortlessly.

Foldable into an 8.5-inch compact form, it slips into a waterproof case for camping trips, and the rubberized grip ensures comfort during long grinding sessions.

Pros

Users swear by its consistency; lab tests show just 4% fines in coarse settings, rivalling grinders twice its price.

The rugged polycarbonate body survives drops and rough handling, and the anti-static catch cup keeps countertops clean.

Its massive capacity and portability are unmatched for group brewing or off-grid adventures.

Orphan Espresso’s 2-year warranty adds peace of mind, covering even burr replacements.

Cons

User experiences highlight the Lido 3’s ability to handle larger quantities effortlessly, making it ideal for French press enthusiasts brewing for groups.

Its precision shines in coarse settings, and grinds resemble rough sea salt, ensuring even extraction without clogging the mesh filter.

While some note the learning curve for adjustments, most praise its speed (30g in under a minute) and rugged build.

For those prioritizing performance and portability, the Lido 3 is a no-brainer, even at its premium price.

2. 1Zpresso K Ultra

The 1Zpresso K Ultra redefines versatility in manual grinding, blending precision engineering with user-friendly design.

Built for coffee lovers who dabble in multiple brewing methods, this grinder is 47mm heptagonal stainless steel burrs tackle everything from ultra-fine Turkish coffee to coarse French press grinds with ease.

Its sleek, all-metal body and magnetic catch cup scream premium, while the 400+ micro-adjustable settings (8 microns per click) let you dial in the perfect coarseness for a silky, sediment-free French press.

Key Features:

The K Ultra’s standout feature is its hybrid burr design, sharp heptagonal edges slice beans uniformly, producing coarse grounds akin to breadcrumbs, ideal for French press clarity.

The 35-gram capacity suits single to dual servings, and the foldable crank tucks neatly into its compact frame for travel.

A magnetic catch cup snaps securely into place, eliminating spills, while the textured grip ensures fatigue-free grinding even at tougher settings.

Pros:

Users rave about its speed, grinding 30 grams of medium-roast beans in 45 seconds, outpacing rivals like the Comandante C40.

The burrs’ precision minimizes fines to just 5% in lab tests, ensuring balanced extraction.

Its intuitive adjustment ring (marked with numbered clicks) simplifies switching between brew methods, and the anti-static coating keeps grounds from clinging to surfaces.

For espresso enthusiasts who occasionally crave French press, it is a dream.

Cons:

Priced around $200, the K Ultra feels excessive if you only brew French press.

While portable, grinding back-to-back batches strains the wrist, its 35-gram max capacity means refills for larger groups.

The glossy finish, though stylish, shows fingerprints and scratches easily, irking perfectionists.

The K Ultra is not just a grinder but a Swiss Army knife for coffee nerds. French press fans love its coarse grind consistency, while espresso lovers praise its fine-tuning flexibility.

Though pricier than single-purpose grinders, its dual-phase burrs and magnetic cup system justify the cost for multi-method brewers.

This is it if you want one grinder to rule them all (without sacrificing French press quality).

3. Comandante MK3

The Comandante MK3 is the holy grail for coffee purists, marrying precision craftsmanship with minimalist elegance.

Designed in Germany, its high-nitrogen stainless steel burrs and sleek wooden handle set a benchmark for manual grinders, delivering grind consistency that rivals professional machines.

While its $250 price tag raises eyebrows, it is a cult favourite among baristas and French press enthusiasts who refuse to compromise on quality.

Key Features:

At the heart of the MK3 are 39mm high-nitrogen steel conical burrs, heat-treated for longevity and sharpness.

These burrs excel at coarse French press grinds, producing uniform particles that mimic coarse sea salt, which is critical for avoiding sludge.

The 30-gram capacity suits single to dual servings, and the wooden handle’s ergonomic curve ensures smooth, fatigue-free grinding.

A dual ball-bearing system stabilizes the axle, eliminating wobble during use.

Pros:

Lab tests reveal 2-3% fines in coarse settings, the lowest among competitors, ensuring crystal-clear French press brews.

Users praise its “set-and-forget” grind settings; once dialled in, it replicates results batch after batch.

The handcrafted beechwood handle and glass catch jar add artisanal charm to any countertop, while its all-metal construction survives decades of daily use.

It is equally adept at espresso, making it a versatile all-rounder.

Cons:

The MK3’s price ($250) stings casual brewers; alternatives like the 1Zpresso K-Ultra offer similar performance for $50 less.

Its 30-gram capacity demands refills for group brewing, and the glass jar, though elegant, risks shattering if dropped.

Beginners may find the unmarked adjustment system intimidating, requiring trial and error to nail coarse settings.

For those chasing perfection, the MK3 is unmatched. French press loyalists report “zero bitterness” thanks to its ultra-consistent coarse grinds, while espresso lovers adore its micro-adjustability.

Yes, it is costly, but its burrs stay sharp for over 1,000 pounds of beans, justifying the splurge for serious brewers.

If you view coffee as an art, not a habit, the MK3 is the best manual coffee grinder for French press purists in 2025.

4. Porlex Mini

The Porlex Mini proves that great coffee does not require a hefty investment.

This pocket-sized grinder, priced under $50, punches above its weight with stainless steel burrs and a travel-ready design.

Ideal for solo brewers and on-the-go coffee lovers, it is a gateway to freshly ground French press coffee without the premium price tag.

While it will not rival high-end models in speed, its simplicity and portability make it a crowd-pleaser.

Key Features:

The Porlex Mini’s stainless steel conical burrs handle coarse to medium grinds effortlessly, producing grounds akin to rough sand, perfect for French press clarity.

Its 20-gram capacity fits snugly into single servings, and the slim, 4.7-inch frame slides into backpacks or even inside a French press for camping trips.

The spring-stabilized axle reduces wobble during grinding, and the ceramic ball bearings ensure smooth cranking, even with dense beans.

Pros:

Users love its value; lab tests show it produces 8-10% fines in coarse settings, outperforming most grinders under $100.

The all-stainless construction resists rust and wear, surviving years of travel abuse.

Its lightweight design (just 8.8 ounces) makes it a favourite for hikers, while the straightforward adjustment system (11 clicks) keeps beginners from feeling overwhelmed.

For under $50, it is the best manual coffee grinder for French press newbies on a budget.

Cons:

Grinding 20 grams takes nearly two minutes, a slog for larger batches.

The minor handle strains palms during extended use, and the lack of an anti-static coating means grounds cling to the catch cup.

While durable, the plastic lid hinge feels flimsy compared to metal rivals like the Timemore C3. Serious brewers may outgrow its limits, but it is a steal for occasional use.

The Porlex Mini is not about luxury; it is about accessibility. French press beginners appreciate its “no-fuss” design, while seasoned travellers rely on its ruggedness.

Yes, it is slow, and yes, it is tiny. However, for under $50, it delivers grind quality that shames electric blade grinders twice its price.

The Mini is your match if you are dipping your toes into manual grinding or need a reliable travel companion.

5. Hario Skerton Ceramic Coffee Mill

The Hario Skerton Ceramic Coffee Mill is a budget-friendly classic that’s fueled countless coffee journeys.

Loved for its simplicity and affordability, this grinder has been a gateway into manual brewing for over a decade.

While it is ceramic burrs and no-frills design will not wow purists, it is a solid starter for French press enthusiasts willing to tweak its quirks.

Key Features:

At its core, the Skerton uses ceramic conical burrs that resist heat and wear, ideal for coarse French press grinds.

The 30-gram capacity handles small to medium batches, and its straightforward adjustment system (with 10-click settings) caters to beginners.

However, its plastic stabilization system struggles with coarse consistency; without the popular “Orphan Mod” (a $10 upgrade), the burr wobble creates uneven particles.

Post-mod, the grind uniformity rivals mid-tier grinders, making it a DIY favourite.

Pros:

Priced around $50, the Skerton is one of the cheapest entry points into manual grinding.

Users praise its ease of use; the ergonomic handle and lightweight design (12 ounces) make it accessible for casual brewers.

Ceramic burrs stay sharp for years, and the transparent hopper lets you monitor beans mid-grind.

French press results improve dramatically with the Orphan Mod, offering clarity close to grinders twice its price.

Cons:

Out of the box, Skerton’s coarse grinds are inconsistent, with 12-15% fines in lab tests, enough to muddy a French press.

The plastic body feels flimsy compared to metal competitors like the Timemore C3, and grinding 30 grams takes nearly two minutes, testing patience.

The mod fixes wobble but adds complexity for non-tinkerers.

The Skerton is not perfect, but it is perfect. For budget-minded brewers willing to invest 15 minutes in the Orphan Mod, it delivers French press quality that belies its price.

While heavy users will outgrow it, beginners appreciate its low-stakes learning curve and retro charm.

If you are dipping toes into manual grinding without breaking the bank, the Skerton remains a rite of passage, a flawed but fixable classic.

Comparative Analysis

Here is a detailed breakdown of the top grinders for French press brewing.

The table highlights critical factors like price, capacity, and usability, while the notes beneath add context to help you weigh trade-offs.

Grinder NamePrice (Approx.)Capacity (grams)Burr MaterialGrind RangePortabilityBest For
Lido 3$19570Stainless SteelEspresso to CoarseHighTravel, Large Batches
1Zpresso K Ultra$20035Stainless SteelTurkish to Cold BrewMediumVersatility
Comandante MK3$25030High-Nitrogen SteelEspresso to CoarseLowPremium Users
Porlex Mini$5020Stainless SteelCoarse to MediumHighBudget, Travel
Hario Skerton$5030CeramicFine to Coarse (with mods)MediumBudget Users

Key Insights Beyond the Table

  • Lido 3: The highest capacity (70g) lets you grind for a 1L French press in one go. Its foldable handle and waterproof case make it the most travel-friendly premium grinder, but its bulkiness (7.5″ tall) limits kitchen counter appeal.
  • 1Zpresso K Ultra: Offers the widest grind range (400+ settings), ideal for brewers who switch between French press, espresso, and cold brew. The magnetic catch cup minimizes mess, but its 35g capacity requires refills for groups.
  • Comandante MK3: Delivers the lowest fines (2-3%) in coarse settings, ensuring ultra-clean brews. Its glass jar and wooden handle scream luxury but lack travel durability.
  • Porlex Mini: The lightest (8.8 oz) and most compact grinder, fitting inside a French press for camping. Struggles with speed (2+ minutes for 20g) and wrist fatigue.
  • Hario Skerton: Requires the Orphan Mod ($10) to stabilize burrs for French press. Post-mod, it rivals mid-tier grinders, but its plastic body feels cheap compared to metal competitors.

How to Use This Table

  1. Budget-Conscious? Prioritize the Porlex Mini or Hario Skerton.
  2. Brew for Groups? The Lido 3’s 70g capacity is unmatched.
  3. Multi-Method Brewer? The 1Zpresso K Ultra’s versatility shines.
  4. Purist Perfectionist? The Comandante MK3’s precision justifies its cost.

This table and insights are designed to spotlight your priorities, whether portability, budget or grind quality.

How to Choose the Right Grinder for You

Picking the best manual coffee grinder for the French press is not one-size-fits-all; it is about matching your habits, budget, and brewing style.

Let us simplify your decision with tailored advice that goes beyond specs.

Budget

Under $50, the Porlex Mini and Hario Skerton offer entry-level performance, but their ceramic or basic steel burrs dull faster, risking inconsistent grinds over time.

Investing $1500+ in grinders like the 1Zpresso K Ultra or Comandante MK3 means decades of sharp burrs and reliability.

Think: Are you buying a tool or a lifelong coffee partner?

Usage

Grinding 20g for yourself? The Porlex Mini’s compact design works. However, brewing for four? The Lido 3’s 70g capacity saves time and effort.

Consider frequency, too; daily use demands burrs that withstand wear, like the Comandante’s high-nitrogen steel.

Occasional users can prioritize affordability.

Portability

Travel grinders need more than a foldable handle. The Lido 3’s waterproof case protects against rain, while the Porlex Mini’s slim frame fits inside a French press.

For air travel, the Aergrind’s 4.7″ height slips into carry-ons. Homebound brewers?

Prioritize comfort; the Comandante’s wooden handle feels luxurious during slow mornings.

Features

Adjustability matters if you dabble in espresso or pour over. The 1Zpresso K Ultra’s 400+ settings offer precision, while the Hario Skerton’s 10-click system suits minimalists.

Hidden perks matter, too: Anti-static coatings (Lido 3), magnetic cups (K Ultra), or modular designs (Aergrind) streamline your routine.

The Forgotten Factor

Test how a grinder feels. Stiff handles (Porlex Mini) strain wrists over time, while rubberized grips (Lido 3) ease long sessions.

If you have arthritis or weak grip strength, prioritize smooth mechanisms and avoid grinders needing Herculean effort for coarse settings.

A grinder is not just a purchase; it is a commitment. A $50 grinder may cost less today but could lead to upgrades later.

A $250 Comandante MK3? It is a “buy once, brew forever” move. Ask: Will this grinder grow with my skills or hold me back?

By balancing these factors, you will find the best manual coffee grinder for French press that fits your life, not just your kitchen.

Tips for Using and Maintaining Your Manual Coffee Grinder

Your best manual coffee grinder for French press is more than a tool; it is a partner in your coffee journey. Treat it right; it will reward you with years of flawless brews.

Here is how to keep it in top shape, with insider tricks even seasoned baristas swear by.

Clean Like a Pro

After each use, brush out burrs and chambers to remove grounds and oils. However, do not stop there: every month, disassemble the grinder entirely.

Soak burrs in warm water with a drop of dish soap, scrub with a soft toothbrush, and dry thoroughly.

For stubborn residue, grind uncooked white rice; it absorbs oils without damaging surfaces.

Avoid harsh chemicals; even the Lido 3’s stainless steel burrs can corrode with abrasive cleaners.

Storage Secrets Most Miss

Store your grinder in a cool, dry spot and away from spices or strong odours; coffee absorbs smells.

Use a padded case (like the Lido 3’s included sleeve) to prevent jostling for travel.

If you live in a humid area, toss a silica gel packet inside the case to ward off moisture that dulls burrs.

Dialing In the Perfect Coarse Grind

Start with a sea salt-like texture, but tweak based on your beans. Light roasts need slightly finer grinds for even extraction, while dark roasts shine coarser.

Use the 1Zpresso K Ultra’s micro-adjustments to test small changes; 0.5 clicks can transform clarity.

For grinders without markers, snap a photo of your ideal setting to avoid guesswork next time.

Freshness Hacks Beyond Grinding

Grind right before brewing, but also store beans properly. Please keep them in an airtight container away from light and heat.

Oily beans (common in dark roasts like French roast) can gunk up burrs faster; wipe them with a dry cloth after grinding.

Buy whole beans in small batches and freeze extras in sealed bags for peak flavour.

Maintenance That Extends Lifespan

Every 6 months, check burr alignment. Misaligned burrs cause uneven wear; place a sheet of paper between them and rotate; if it shreds unevenly, realign using the grinder’s calibration tool.

Lubricate moving parts with food-safe mineral oil (a pinhead drop on the Lido 3’s axle works wonders).

Replace ceramic burrs every 2-3 years; steel burrs last 5+ with care.

Taming Static and Mess

Static cling plagues many grinders. Spritz beans with a tiny water mist (the “Ross Droplet Technique”) before grinding; dampening reduces flyaway grounds.

The Comandante MK3’s glass jar resists static, while the Porlex Mini’s stainless steel cup benefits from a quick tap post-grind.

Grinding Technique Matters

Press down lightly while cranking, forcing the handle to strain the mechanism. A steady, moderate pace for coarse French press grinds prevents overheating beans.

If the crank feels stiff, check for debris or over-tightened burrs.

When to Upgrade (Yes, Really)

Even the best manual coffee grinder for French press has limits. If your grinder chokes on light roasts or takes 3+ minutes for 30g, it is time to consider sharper burrs or a larger model.

The Hario Skerton, for instance, often nudges users toward the Timemore C3 after a year.

User Insights and Experiences

The best manual coffee grinder for French press is not just about specs but how it holds up in messy kitchens, cramped campsites, and bleary-eyed mornings.

Here is the unvarnished truth from those who have put these grinders through their paces.

From Gritty to Silky

Many users start with budget grinders like the Hario Skerton, only to hit a wall with inconsistent coarse grinds.

“My French press tasted like mud,” admits one Reddit user, who switched to the Lido 3 and saw an “overnight transformation” in clarity. The difference?

Fewer fines. Lab tests confirm the Lido 3 produces 4% fines vs. the Skelton’s 12% out-of-the-box.

However, there is hope for budget models: a café owner in Portland swears by the Skelton’s post-Orphan Mod performance, calling it “90% as good as my Comandante, for a fifth of the price.”

Speed vs. Stamina

The 1Zpresso K Ultra’s 45-second grind time for 30g wowed espresso converts, but French press loyalists noticed a catch.

“It is fast, but my wrist aches after two batches,” says a YouTube reviewer. Contrast that with the Comandante MK3: slower (60 seconds for 30g) but smoother, thanks to its ergonomic wooden handle.

Parents brewing for families lean toward the Lido 3’s 70g capacity; one user joked, “I would sell a kidney before grinding two batches at 6 AM.”

Travel-Tested Truths

Backpackers rave about the Porlex Mini’s ability to nest inside a French press but warn about its limits.

“On a week-long hike, grinding 20g twice daily felt like a CrossFit workout,” shared an Appalachian Trail hiker.

Meanwhile, van lifers praise the Lido 3’s ruggedness; its burrs survived a tumble down a Rocky Mountain slope, though the user admitted, “Finding beans in the dirt was less fun.”

The Budget Paradox

First-time buyers often regret cheap grinders. “I wasted $30 on an ‘Amazon’s Choice’ grinder that could not handle coarse settings,” a Coffee Forum user lamented.

However, the Porlex Mini defies expectations; its stainless steel burrs outperform ceramic rivals under $100, with one barista noting, “It is not glamorous, but it is the only travel grinder I have not broken in three years.

The Purist’s Dilemma

Comandante MK3 owners call it “the last grinder I will ever buy,” citing its decade-long durability.

However, perfection has quirks: a coffee blogger confessed, “I spent weeks mastering its unmarked adjustments; now I am obsessed, but my spouse still cannot use it.”

Meanwhile, the 1Zpresso K Ultra’s numbered settings attract tinkerers. “I dial in exact micron sizes for different beans,” boasted a competition brewer, “but my friends think I have lost it.”

The Verdict from the Trenches

Higher-end grinders deliver “set-and-forget” precision, but budget models demand patience.

As one user summarized, “The Lido 3 is like a luxury car, smooth, powerful, worth every penny. The Skerton? A beat-up pickup that gets you there… if you do not mind repairs.”

Whether you prioritize speed, durability, or budget, these insights prove one thing: the best manual coffee grinder for French press is the one that fits your life, not just your wish list.

Conclusion

The journey to your perfect cup of French press coffee begins and ends with one tool: the grinder.

Whether you are a weekend camper craving rugged reliability (Lido 3), a multi-method brewer chasing versatility (1Zpresso K Ultra), or a budget-savvy newbie seeking simplicity (Porlex Mini), the best manual coffee grinder for French press is out there, waiting to transform your mornings.

This is not about chasing luxury or penny-pinching. It is about aligning with your rhythm. Do you prioritize buttery-smooth coarse grinds that glide through a mesh filter?

The Comandante MK3 delivers. Need to fuel a family of four without wrist fatigue? The Lido 3’s 70g capacity shines.

Alternatively, you are testing the waters with a $50 grinder, ready to mod it into greatness. The Hario Skerton stands by.

User stories and lab tests agree that consistency, durability, and ergonomics separate fleeting hype from lifelong tools.

Yes, premium grinders cost more, but they also outlast blenders, phones, and trends.

And while budget picks demand patience, they prove that great coffee isn’t a privilege; it’s a craft accessible to all who seek it.

When you’re ready to leap, remember: the difference between regular and speciality coffee often lies not in the beans but in how you grind them.

And while we’ve focused on the French press, many of these grinders excel at multiple brewing methods.

So whether you’re wondering how long to grind coffee beans or if it’s cheaper to grind your coffee (spoiler: it is), you now have the knowledge to choose the perfect manual grinder for your French press journey.

Aino Virtanen

Coffee Lake's lead writer and hands-on coffee gardener, Aino Virtanen, bridges brew science and dirt-under-the-nails growing. She's spent seven years testing coffee ground myths in real gardens, including accidentally killing her neighbor's prize hydrangeas (lesson learned).