A clearer way to get unstuck

Everyday tools. Clear answers.

BiyoTool brings together free calculators, converters, generators, date and time tools, text tools, finance and health tools, and practical browser utilities. Fast, private, and ready without sign-up.

Fast, local, no sign-in177 browser tools, ready when you are

Decision engine

iPhone Decision Engine

Should you keep, upgrade, or wait? Compare your current phone, priorities, and estimated cost for an explainable recommendation.

Runs locally. No built-in prices or retailer offers.

Try the decision engine

Useful tools

Everyday essentials ready in your browser.

View all

Age Calculator

Free age calculator to calculate an exact age from a date of birth and a comparison date, shown in years, months, and days.

BMI Calculator

Free BMI calculator to estimate body mass index from height in centimetres and weight in kilograms, then view its reference range.

Percentage Calculator

Free percentage calculator to solve common percentage questions, including a percentage of an amount, a part of a whole, or change between values.

Loan Calculator

Free loan calculator to estimate monthly repayments, total repayment, and interest.

Loan & EMI Calculator

Free loan and EMI calculator to estimate monthly repayments, total interest, total repayment, and an amortisation schedule from your loan amount, interest rate, and term.

Colour Codes

Free colour codes tool to pick, explore, compare, and copy colour codes for websites, apps, and digital designs.

Image to WebP Converter

Free image to WebP converter to convert JPG, PNG, GIF, BMP, and other supported images in your browser. Adjust quality, compare file sizes, and download your WebP image privately.

Days Between Dates Calculator

Count the exclusive days, weeks, and hours between two dates.

QR Code Generator

Free QR code generator to turn a link or short message into a scannable code.

Password Generator

Free password generator to make a strong, private password in your browser.

Tip Calculator & Bill Split

Free tip calculator to work out the tip and split a bill across any number of people.

Mortgage Calculator

Free mortgage calculator to estimate monthly payments for a home purchase or refinance.

Time Zone Converter

Convert a date and time between common time zones.

Temperature Converter

Free temperature converter to convert Celsius, Fahrenheit, and Kelvin instantly.

Word Counter

Free word counter to count words, characters, sentences, and reading time.

Unit Price Calculator

Find the price per item, weight, volume, or other quantity.

Private where it counts.

Calculations happen in your browser. Your inputs stay yours. BiyoTool does not need an account to be useful.

Explore tools

Good to know

Frequently Asked Questions

Quick answers about using BiyoTool.

Yes. The current BiyoTool library is available without payment or a subscription.

No. You can open and use the tools without signing in.

Yes. Tool pages and controls are designed to work across mobile, tablet, and desktop screen sizes.

BiyoTool calculations and transformations run in your browser. The tools do not need to upload your entries to calculate a result.