R3CK0N
Math mode is a free timed arithmetic drill that runs in your browser: addition, subtraction, multiplication and division against the clock, with no signup and nothing to install.
Pick an operation and a difficulty, choose how long to run, and type answers as fast as you can. When the run ends you get your speed in correct answers per minute, your accuracy, a speed tier, and whether you beat your own best at that drill. Every run is saved on your device. An account is optional, and only needed if you want your history to follow you between devices.
Choose a drill. Addition, Subtraction, Multiplication or Division on their own; Custom, a blend of the four weighted however you like; or Focus, which leans on the operations you miss or answer slowest and brings a missed problem back a few questions later. The same screen also holds the GRE Quant drills (percents, fractions, powers, algebra and stats), two quant-interview drills (Sequences and Estimation), a two-minute Sprint, and every times table from 2 to 12.
Choose a difficulty. Four levels, and each one changes the numbers, not the rules:
Division always has a whole-number answer, so you are practising mental division, not long decimals.
Choose a length. A timed run of 15, 30, 60 or 120 seconds, or 5 or 10 minutes for holding a pace; or a fixed number of problems, anything from 1 to 999. The next problem appears the moment your answer is complete, so there is no Enter key to press and no time lost between problems.
Read your score. Speed is ppm: correct answers per minute of answering time. Accuracy is right answers over everything you answered. Each result lands in one of five speed tiers for its difficulty, Warming up, Steady, Quick, Sharp or Lightning, and tells you how many more ppm reach the next one. On Medium the bands start at 5, 10, 15 and 22 ppm; on Easy at 10, 20, 30 and 40. Your best at each drill and difficulty is kept, and you can race its ghost on your next run.
Say you run Multiplication on Medium for 60 seconds. The ninth problem is 37 × 24. Work left to right: 37 × 20 is 740, 37 × 4 is 148, and 740 + 148 = 888. Type 888 and the tenth problem is already up.
The clock runs out after 14 problems, 12 of them right. Speed is 12 correct answers in one minute, so 12 ppm; accuracy is 12 of 14, which rounds to 86%. On Medium that is the Quick tier, 3 ppm short of Sharp. Run it again tomorrow and the result screen shows whether you beat your 12.
It is free, with no ads and no paywall, and you can play without signing up. Your runs are saved in your browser. Signing in is optional: it syncs your history across devices and lets the Stats screen compare you with other players.
Problems per minute, counting only correct answers, measured over the time you spent answering. Twelve right in a 60-second run is 12 ppm. The raw figure, every answer right or wrong, is shown underneath it.
Easy if your times tables are solid, Very easy if they are not. Move up when you reach Sharp on your current level. The tier bands are set per difficulty, so each level has its own targets to chase.
Yes. Choose Custom, keep all four operations, and set the length to 120 seconds. The Zetamac alternative guide walks through it.
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