Practice gives you a fixed number of untimed questions with immediate answer feedback. Timed Round asks you to complete as many conversions as possible before the round clock expires. Speed Challenge gives every question its own time limit.
Difficulty changes the volumes being converted. Easy uses whole numbers from 2–100 liters or 1–25 US gallons. Medium uses one decimal place from 2.0–300.0 liters or 0.5–80.0 US gallons. Hard can use two decimal places from 2.00–2000.00 liters or 0.25–500.00 US gallons.
Answer Precision controls how your answer is rounded. One US liquid gallon equals exactly 3.785411784 liters. To convert liters to US gallons, divide by 3.785411784; to convert US gallons to liters, multiply by 3.785411784. The app uses exact rational arithmetic, then checks whether your numeric answer rounds to the required precision.
Gallon type: this practice uses US liquid gallons. Imperial gallons use a different conversion relationship.
When Both Directions is selected, questions alternate unpredictably between liters-to-US-gallons and US-gallons-to-liters. Equivalent numeric formatting is accepted, so an answer such as 62.10 is treated the same as 62.1 when appropriate.
You can press Enter to submit, P to pause, or Esc to end the current round. Timers pause automatically when the page is hidden.