SOROBAKSpeed Run

Choose the next step

Choose the number
range

Apply the friends-of-five formulas in rapid sequences and strengthen mental calculation.

F5 Selected modeFriends of 5

4 levels

Where should we start?

Choose a comfortable number range. You can set the speed and number of problems on the next page.

One digit

Fast, confident calculation with one digit

Two digits

Focus training with two-digit numbers

Three digits

Larger numbers and a stronger memory

Four digits

Maximum speed and accuracy