Mental math under a metronome beat.
Practice mental math while holding a steady metronome rhythm.
Dern-Jood Paper
Open or download the Dern-Jood paper sheets for offline practice.
90 BPM
Set the math difficulty and BPM yourself. Each question gives more or less time based on its complexity.
Random 50-180 BPM
BPM changes from question to question and math difficulty is mixed. Answer before each adaptive timer runs out.