Frequently Asked Questions

Yes, this game will always be free to play. No advertisements, no sponsored content.

Speed Rating measures how quickly and accurately you solve problems. It's calculated as: (correct answers) / (time in seconds). A higher Speed Rating means you're solving more problems correctly in less time.

Problems are generated using a seeded random number generator, which ensures fairness and reproducibility. Each game session has a unique seed, and the same seed will always produce the same set of problems.

Easy: Within-system conversions (g/kg, cm/m, mL/L) with round numbers. Medium: Adds cross-system pairs (km/mile, L/gallon) and temperature conversions. Hard: All unit pairs including oz/g, ft/cm, fl oz/mL, pint/L, and more. Expert: Same pairs as hard but with trickier numbers including decimals.

Answers are compared after rounding to 2 decimal places. For example, if the correct answer is 2.205, entering 2.20 or 2.21 would both be accepted. You don't need to match every decimal place exactly.

Weight: grams, kilograms, ounces, pounds. Length: centimeters, meters, kilometers, inches, feet, yards, miles. Volume: milliliters, liters, fluid ounces, cups, pints, quarts, gallons. Temperature: Celsius and Fahrenheit (medium difficulty and above).

Unit conversions require more mental work than arithmetic, so 10 problems keeps each round manageable while still being a meaningful challenge.

You don't have to sign in to play. Signing in lets you track your game history and see your progress over time. Games are counted in global statistics even without signing in.

If you're signed in: your email, when you play, the difficulty level, time taken, and score. If not signed in: only that someone played a game at a given time.

Memorize the key conversion factors (1 kg = 2.205 lb, 1 mile = 1.609 km, 1 gallon = 3.785 L, C = (F-32) x 5/9) and practice regularly. Start with easy mode and work your way up.