About

ToolHarbor is a collection of 72+ free online tools: unit and currency converters, investing and loan calculators, image and PDF tools, generators and device tests. Every tool is free, needs no account and is built to load fast on any phone or computer.

How we keep results accurate

• Unit conversions use the exact legal definitions of each unit: the International System of Units (SI), the 1959 international yard and pound agreement, and the US customary and UK imperial definitions. Each converter page states the factors it uses.
• Financial calculators use the standard textbook formulas for compound growth, annuities and loan amortisation, and every calculator page shows its formula so you can check the result yourself.
• Health calculators follow published references: World Health Organization BMI categories and the Mifflin–St Jeor equation.
• Exchange rates are daily mid-market reference rates from ExchangeRate-API, shown with the date of the last update.

Your privacy

Image, PDF, text and device tools run entirely inside your browser. Your files, text, camera and microphone input are processed on your own device and are never uploaded to us. See the privacy policy for details.

Limits

The calculators are for general information and planning. They are not financial, tax, medical or legal advice. For decisions that matter, confirm the figures with a qualified professional or the relevant institution.

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