Consulting maths trainer
Sharpen the mental maths skills consulting interviews demand — large-number arithmetic, ratios, percentages, fractions, and the Rule of 72. Pick a drill mode, set your timer and tolerance, and go. Everything runs in your browser.
🎯 Drill modes
Arithmetic & conversionLarge-number operations with K / M / B suffixes
+
−
×
÷
Ratio simplificationReduce large ratios to lowest terms
Percentage changeCalculate the % change between two values
Percentage ofX% of a large figure
Fractions ↔ percentagesConvert common fractions and percentages
Rule of 72 / CAGRDoubling time and required return
Random modeA mix of all question types above
⏱ Timer
± Tolerance
±10%
Accepts answers within this margin. Ratios and fraction conversions always require exact matches.