Simple tools that get things done
17 free calculators. No account, no uploads — every calculation runs in your browser.
Money
Mortgages, loans, savings and interest — worked out plainly.
- Mortgage Calculator Work out the monthly payment on a repayment mortgage, and what it costs in total.
- Loan Calculator See the monthly repayment on a fixed-rate loan, and what the interest adds up to.
- Compound Interest Calculator See what a starting amount and a monthly contribution grow to, and how much of it is interest.
- 50/30/20 Budget Calculator Split your monthly take-home pay into needs, wants and savings with the 50/30/20 rule — or your own percentages.
Business
Margins, markup, VAT and the numbers a business runs on.
- Profit Margin Calculator Turn a cost and a selling price into profit, profit margin and markup — all three at once.
- Markup Calculator Add a markup to a cost to get the selling price, and see the profit and the margin it leaves.
- VAT Calculator Add VAT to a price or take it back out of a VAT-inclusive one, at whatever rate you set.
Work
Salaries, rates and what your time is actually worth.
Dates & Time
Working days, durations and deadlines.
Converters
Units and formats, converted exactly.
Health & Family
Readings, cycles and ages — explained plainly, never a diagnosis.
- Blood Pressure Chart & Reading Checker Enter a reading and see which blood-pressure category it falls in, using the standard American Heart Association chart.
- Ovulation & Fertile Window Calculator Estimate your ovulation day, fertile window, next period and due date from your last period and cycle length.
- Baby Age Calculator — weeks, months & corrected age How many weeks and months old your baby is today, plus corrected age if they arrived before their due date.
Home & Everyday
What your car, pets and subscriptions really cost and mean.
- Dog & Cat Age Calculator — pet years to human years Convert your dog's or cat's age into human years using the size-based chart vets use, not the old “× 7” rule.
- Car Running Cost Calculator — cost per year & per km Work out what your car really costs to run each year, each month and per kilometre — fuel, insurance, tax, servicing and depreciation.
- Subscription Cost Calculator — what it really costs per year Turn any weekly, monthly or quarterly price into its yearly cost, and see the total over several years with price rises.
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