About Freentar

Freentar is a collection of free online tools: calculators, unit converters, side-by-side comparisons, date & time tools, and searchable reference tables.

Three promises, on every page:

• Instant. Every tool runs entirely in your browser. No spinners, no server round-trips.
• Free. No accounts, no signups, no paywalled features.
• Honest. Formulas and sources are stated plainly, and estimates are labeled as estimates.

How the site is built

Freentar is a static site — each page is pre-built HTML with a small amount of JavaScript for interactivity, which is why pages load fast. The catalog grows regularly as we identify tools people are searching for.

Spotted an error in a formula or a table? Please tell us — accuracy matters more to us than anything else on this site.