About ToolsLabOnline

ToolsLabOnline is a collection of free online calculators and tools built for everyday math: what a loan will cost you, what you earn per hour, how many days are left until a date or what a percentage comes to.

How we work

• Every tool shows its work. Next to each calculator you will find the formula used, a worked example and the limits of the result.
• Private by design. Calculations run in your browser. The numbers you enter are not sent to our servers or stored.
• Localized, not just translated. English versions are built for the United States and Spanish versions for Spain, each with its own currency, units and rules.
• No sign-up. Every tool works without an account.

Who is behind it

ToolsLabOnline is an independent project created and maintained by Rafael Verdugo Durán. The site is supported by advertising, which keeps every tool free to use.

Important notice

Results are estimates. They are not financial, tax, legal or medical advice. Talk to a qualified professional before making an important decision.

Contact

Found a mistake or want to suggest a new tool? Email us at rafa@rafaelverdugo.com.