ConverterToolkit

About Converter Toolkit

Converter Toolkit is a free online unit conversion service. It converts between kilograms and pounds, Celsius and Fahrenheit, centimeters and inches, and other measurement units that people search for thousands of times every day. Every result uses the exact, internationally-defined conversion constant — never an approximation.

Why exact matters

Most online unit converters use truncated factors like "1 kg ≈ 2.2 lbs" or "1 inch ≈ 2.5 cm". Those rounded numbers are fine for casual estimates but wrong for cooking, fitness tracking, engineering, pharmacy, and shipping calculations. Errors compound when you chain conversions or work with large quantities.

Converter Toolkit uses the constants defined by the BIPM (Bureau International des Poids et Mesures) and the NIST (US National Institute of Standards and Technology). The factors haven't changed since 1959 — they're the same numbers your scale, ruler, and thermometer were calibrated to.

Exact factors used

  • 1 lb = 0.45359237 kg (BIPM, 1959)
  • 1 inch = 2.54 cm (International Yard and Pound Agreement, 1959)
  • °F = °C × 9/5 + 32 (algebraically exact)
  • K = °C + 273.15 (SI definition)

How the site is built

Every page is pre-rendered as static HTML at build time. No JavaScript is needed to read the answer — the result, formula, and reference tables are in the HTML itself. The interactive calculator on each page is progressive enhancement: it works in any modern browser, but the page already shows the conversion before it loads.

Pages are served from Cloudflare's global edge network — typically <100 ms response time anywhere in the world. No tracking pixels, no analytics scripts, no third-party fonts loaded after the page renders.

What's on the site today

Coming next

Area, volume, speed, data-storage, time, pressure, and energy converters are planned. Each will use the same approach: exact SI-defined constants, pre-rendered pages, no signup, no ads.

Reporting an issue

Found a wrong number, broken link, or page that won't load? Open an issue on the project repository or send feedback through the contact information in the site's GitHub. Every issue is reviewed.

See also: Privacy · Terms of use