Nine calculators for the maths that comes up day to day — splitting a bill, working out a tip, converting units, checking your BMI, and what a full tank or a car journey actually costs. All calculations run locally in your browser, with no sign-up.
Which one do I need?
Common questions
Does the split bill calculator handle uneven shares?
Yes — alongside an equal split with tip, there's an itemized mode where you assign specific items to specific people, so the total each person owes reflects what they actually ordered.
What BMI ranges does the calculator use?
The standard WHO bands — under 18.5 underweight, 18.5–24.9 healthy weight, 25–29.9 overweight, 30+ obese. BMI is a population-level screening measure, not a diagnosis, so treat the category as a starting point rather than the final word.
How does the running pace calculator work if I only know two figures?
Enter any two of distance, time and pace and it solves for the third, then shows your speed and even splits — useful for working out a target pace before a race or checking your actual pace afterwards.