Free Coffee
Brewing Tools
Precision instruments for better coffee. Convert grind settings, calculate brew ratios, and dial in your perfect cup — all free, no sign-up required.
Grind Size Converter
Translate grind settings between 55+ popular grinders instantly. Switch from a Comandante to a 1Zpresso, Baratza to a Fellow Ode — no guesswork.
Open Tool →Brew Ratio Calculator
Calculate the perfect coffee-to-water ratio for any brew method. Dial in V60, Chemex, AeroPress, French press, espresso, and cold brew.
Open Tool →More tools coming soon
Extraction timer, water chemistry calculator, and more.
Everything you need to brew better
Grind Size Converter
- Covers 55+ grinders from Baratza, Comandante, 1Zpresso, Fellow, and more
- Convert from any grinder or from brew method (espresso, pour over, French press)
- Visual grind scale showing fine to coarse on a 0–100 index
- Quick reference table comparing all grinders at once
Brew Ratio Calculator
- Pre-set ratios for 7 popular brew methods
- Adjustable ratio slider for fine-tuning (1:15 to 1:18)
- Instant results: dose, water, grind index, and brew time
- Brew method reference guide with recommended parameters
Built for coffee people, by coffee people
No sign-up required
Every tool works instantly in your browser. No account, no paywall, no ads.
Real calibration data
Grind conversions are based on actual grinder measurements — not rough estimates from forums.
Works on any device
Fully responsive. Use at the kitchen counter, coffee bar, or anywhere you brew.
Frequently asked questions
Are these coffee tools really free?
Yes — every tool on BrewMark is 100% free with no sign-up required. We built these because we believe better tools make better coffee, and great coffee should be accessible to everyone.
How does the grind size converter work?
Our grind converter uses a universal 0–100 grind index that maps every grinder's settings to a shared scale. We've calibrated 55+ grinders by mapping their espresso, filter, and coarse anchor points. Select your source grinder and setting, choose a target grinder, and get an instant conversion.
What brew ratios should I use?
It depends on the method. Pour over and drip typically use 1:15 to 1:17 (coffee to water by weight). Espresso runs around 1:2. French press is usually 1:15. Cold brew concentrate goes as strong as 1:5. Our brew calculator has pre-set ratios for each method that you can fine-tune.
Can I use these tools on my phone?
Absolutely. Every tool is fully responsive and works on any device. For the best experience, download the BrewMark app — it has every tool built in plus AI-powered recipe adaptation for your exact equipment.
How accurate is the grind size conversion?
Our conversions are based on real calibration data from each grinder, mapped to anchor points (espresso, filter, coarse). Results are a reliable starting point — you may need to adjust by one or two clicks depending on your beans, altitude, and water chemistry.
Will you add more tools?
Yes. We're working on an extraction timer, water chemistry calculator, and a dose-by-cup-size tool. Subscribe to our newsletter to get notified when new tools launch.
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Embed these tools
on your website
Help your customers brew your coffee perfectly. Add grind converters, brew calculators, and personalized recipes to your product pages — no code required.
Learn More →All tools built into the app
The BrewMark app has every tool built in — plus AI-powered brew recipes tailored to your exact grinder and taste preferences.