Calculators that show their work
Free, fast and accurate tools for everyday questions — from coffee ratios and recipe scaling to EV charging costs and visa day counts. Every result explains the math behind it.
Food & Drink
- Pour Over Coffee Ratio CalculatorDial in coffee and water grams for V60 and other pour over brewers.
- Espresso Ratio CalculatorWork out dose, yield and brew ratio for any espresso shot.
- French Press Coffee Ratio CalculatorCoffee and water grams for any size French press, brewed to your strength.
- AeroPress Ratio CalculatorCoffee and water grams for AeroPress, from full cups to concentrate.
- Cold Brew Coffee Ratio CalculatorCoffee, water and dilution for cold brew concentrate or ready-to-drink.
- Moka Pot Coffee Ratio CalculatorCoffee and water for any size stovetop moka pot.
- Cups to Grams ConverterAccurate cup-to-gram weights for dozens of common ingredients.
- Flour Cups to Grams ConverterPrecise gram weights for flour, sugar and butter when baking.
- Recipe Serving Size ConverterScale ingredients up or down for any number of servings.
- Recipe Cost CalculatorCost per serving and a suggested menu price for any dish.
- Neapolitan Pizza Dough CalculatorFlour, water, salt and yeast for authentic Neapolitan dough balls.
- New York Style Pizza Dough CalculatorFlour, water, oil and sugar for foldable New York slices.
- Pan Pizza Dough CalculatorHigh-hydration dough for Sicilian, Detroit and pan pizzas.
Hobbies & Crafts
- 3D Printing Filament Cost CalculatorEstimate filament weight, length and cost for any 3D print.
- Aquarium Stocking CalculatorTank volume and a rough fish-capacity estimate from your dimensions.
- ND Filter CalculatorFind the corrected shutter speed for any neutral density filter.
- Exposure Value (EV) CalculatorFind the EV of any aperture, shutter and ISO combination.
Beauty & Fashion
- Makeup Expiration CalculatorWork out the replace-by date for opened makeup and skincare.
- Ring Size ConverterConvert ring sizes across US, UK, EU and Japan systems.
- Ring Size by Diameter CalculatorTurn an inside diameter or circumference in mm into a ring size.
- Women's Clothing Size ConverterConvert women's dress and top sizes across US, UK and EU.
- Men's Clothing Size ConverterConvert men's jacket and shirt sizes across US, UK and EU.
Climate & Environment
Shopping
Automotive & EV
- EV Home Charging Cost CalculatorWork out the real cost of charging your EV at home.
- EV Public Charging Cost CalculatorTotal cost of a public charge, including session and time fees.
- EV Charging Time CalculatorEstimate charging time from battery size, charge level and power.
- EV Charging Time by Level CalculatorCharging time by charger level: L1, L2 and DC fast.