Free online tools. No sign-up, no uploads.
Calculate, convert and generate — everything runs in your browser, so what you type stays with you.
Pick a shelf, find your tool.
Math & finance
Percentages, loans, interest and everyday sums.
→Text & writing
Count, clean and transform your text.
→Developer tools
Format, encode and generate, all locally.
→Converters
Units of every kind, in both directions.
→Health & fitness
Quick estimates for everyday health numbers.
→Date & time
Differences, ages, timestamps and schedules.
→Color & design
Pick, convert and check colors.
→Web & SEO
Small helpers for site owners and marketers.
→Home & DIY
Areas, paint and materials for a project.
→Images
Compress, resize and convert images on your device.
→Cooking
Scale recipes and convert kitchen measures.
→School & study
Grades, GPA and test scores.
→Car & travel
Fuel, trip costs and travel times.
→Most used tools
The tools people open most. Every one runs in your browser.
Percentage calculator
Find a percentage, a change or a share of a total.
→Loan calculator
Monthly payment, total interest and the payoff schedule.
→Word counter
Words, characters, sentences and reading time.
→JSON formatter
Validate, prettify and minify JSON.
→Password generator
Strong passwords, created on your device.
→Unit converter
Length, weight, temperature, volume, area, speed and data.
→BMI calculator
Body mass index from height and weight.
→Color converter
HEX, RGB, HSL and CMYK in one place.
→Compound interest calculator
See how savings grow with interest and regular deposits.
→Mortgage calculator
Monthly payment with taxes, insurance and down payment.
→Scientific calculator
Trigonometry, powers, roots and logs.
→QR code generator
QR codes for links, text, Wi-Fi and contacts.
→Image compressor
Make photos smaller without uploading them.
→Fuel cost calculator
What a trip costs in fuel, split between people.
→Simple on purpose
Private by design
Everything runs in your browser. We never see what you type.
Instant results
No page reloads, no waiting, no account to create.
Explained, not just solved
Each tool comes with the formula and a plain-language explanation.
Guides
How to calculate a loan payment
The standard monthly payment formula, a worked example and what drives the total cost.
Read →FinanceCompound interest, explained simply
How interest on interest works, why time matters most, and a quick way to estimate doubling time.
Read →MathHow to calculate percentage change
The formula, three examples and the mistake everyone makes.
Read →What should we build next?
Describe the tool you wish existed. We read every suggestion.