About ToolsKingMaster

ToolsKingMaster is an independent website that makes free, fast and private online tools for everyday tasks — calculating a loan payment, merging PDFs, converting units, counting words and much more. It is built and run from the Houston, Texas area by a small-business owner who got tired of tool sites that were slow, cluttered or quietly uploaded people's files.

What makes our tools different

• Private by design. Calculations and file processing run inside your browser. Your numbers, text, PDFs and images are not uploaded to our servers.
• Explained, not just answered. Every tool page shows the formula or method it uses, a worked example and answers to common questions, so you can check the result yourself.
• Free and open to everyone. No account, no paywall and no limits on how often you use a tool.

How we build and check the tools

Each tool uses published, standard methods — for example, the amortization formula used by lenders for fixed-rate loans, the internationally defined conversion factors for units, and the Mifflin-St Jeor equation for resting energy. Before a tool is published we test it against known worked examples and edge cases, and we re-review tool pages periodically; the "last reviewed" date appears at the bottom of each page.

If you ever spot an error or a result that doesn't look right, please tell us — corrections are fixed quickly.

How the site is funded

ToolsKingMaster may show advertising to cover hosting and development costs. Ads never change how a tool calculates, and we don't sell your personal information. See our privacy policy for details.

Important note

Our calculators provide estimates for information and planning. They are not a substitute for advice from a qualified financial, legal, tax or medical professional. Read our full disclaimer.