Calculateyour BMI.
Dozens of calculators with live results — and a look at how you compare with everyone else. Anonymous, no account.
Not just a number.
Every result can be seen against everyone else’s — percentiles and distributions built from anonymous statistics. The more people calculate, the smarter the comparisons get.
Live results
Results update as you type — no “calculate” button, no page reloads.
Anonymous comparisons
Percentiles and distributions against other users. No account, no personal data.
Tested accuracy
Every calculator ships with tested reference cases; formulas and sources are on its page.
Free, in three languages
No sign-up, no limits. English, Polish and Spanish — with local market rules.
Health
Numbers about your body without the guesswork — weight, calories and more, each result with an interpretation instead of a bare figure, plus a look at where you stand compared to others.
All Health calculators (9) →Calculate your BMI (body mass index) and see how it compares to WHO recommendations.
Find your BMR and TDEE (maintenance calories), then see exactly how many calories to eat to lose, maintain, or gain weight.
Estimate your baby's due date from your last period, conception or ultrasound — plus current week and trimester.
Estimate your fertile window, ovulation day and predicted next period from your last period date and cycle length.
Calculate your body fat percentage with three methods — US Navy, RFM and BMI — from a single set of measurements.
Finance
Make money decisions on real numbers — savings growth, loans and overpayments laid out year by year, with charts and the real impact of every choice.
All Finance calculators (5) →See how your savings grow with compound interest — with or without regular contributions.
Work out your monthly payment and total cost, then see how much you save by shortening the term or lowering the payment when you overpay.
Calculate your full mortgage payment (PITI): principal and interest, property tax, insurance, PMI/UNWW — for the US, Poland and other markets.
Project how much you'll have saved for retirement, set an income goal, and see how much you need to contribute to close the gap.
Split your net income into needs, wants and savings using the 50/30/20 rule, try a high-cost-of-living variant or your own ratio, and see how your actual spending compares.
Everyday life
Everyday questions that aren’t worth hunting formulas for — dates, ages and quick conversions, answered in a second.
All Everyday life calculators (7) →Find out exactly how old you are in years and days, and how long until your next birthday.
Count the exact days, weeks, months and years between two dates — with business days and date add/subtract.
Work out how much a single appliance or your whole electricity bill costs — kWh usage, day/night rates, standing charge and CO2 footprint.
Fuel cost calculator — estimate how much a trip or commute costs in fuel from distance, efficiency and price per gallon or liter.
Convert fuel economy between L/100km, MPG (US), MPG (UK/imperial) and km/L — all four at once, from a single value.
Math
The math you actually meet — percentages, ratios and shares in several variants at once, no formula recall required.
All Math calculators (13) →Work out what X% of a number is, and what percentage one number is of another.
Add, subtract, multiply or divide two fractions (or mixed numbers) — simplified, as a mixed number, and as a decimal.
Simplify a ratio, solve a proportion, scale a ratio, split an amount by ratio, or convert a ratio to a fraction and percentage.
Find the square root of any number — plus nth root, cube root, decimal precision control, and simplified radical form (e.g. √72 = 6√2).
Raise any number to a power — including negative and fractional exponents, with step-by-step expansion for integer powers and clean handling of 0⁰, division-by-zero, and complex-root edge cases.
Conversion
Unit converters built on exact factors — type a value once and see every unit at a glance, from centimeters to feet to miles.
All Conversion calculators (2) →Most popular calculators
What people reach for most often.
Calculate your BMI (body mass index) and see how it compares to WHO recommendations.
Work out your monthly payment and total cost, then see how much you save by shortening the term or lowering the payment when you overpay.
See how your savings grow with compound interest — with or without regular contributions.
Work out what X% of a number is, and what percentage one number is of another.
Find out exactly how old you are in years and days, and how long until your next birthday.
How it works
- 1
Find a calculator
Type what you want to calculate, or browse a category.
- 2
Enter your numbers
The result updates live, with an interpretation and a chart where it helps.
- 3
Compare with others
See percentiles and distributions — anonymously, no account.
How we keep the numbers right
Every calculator on Davided has a set of reference cases — hand-checked results that automated tests verify before every release. Formulas and sources are listed on each calculator’s page, along with the date it was last reviewed.
Found a mistake? Write to kontakt@davided.pro.
Frequently asked questions
Are Davided calculators free?
Yes — every calculator on Davided is completely free, with no account, no limits and no paywall. You open a calculator, type your numbers and get the result instantly.
How do I know the results are correct?
Every calculator ships with a set of reference cases that is tested automatically before each release. Each calculator page also lists the formulas and sources it is based on, along with the date it was last reviewed.
How do anonymous comparisons work?
When you use a calculator, your result can be compared against aggregated results of other users — as percentiles and distributions. No account is needed and no personal data is stored; only anonymous aggregate statistics are kept.
What languages and countries does Davided support?
Davided is available in English, Polish and Spanish, each written natively rather than machine-translated. Country-specific calculators (like tax or salary tools) appear only in the languages where they make sense.
Can I report a mistake or suggest a calculator?
Yes, please do — write to kontakt@davided.pro. Corrections go through the same reference-case testing as every other change before they are published.