AllUnits.net is a free online unit-conversion service built around a single mission: make accurate, fast, and accessible unit conversion available to everyone, in their own language, without friction, paywalls, or sign-ups. Whether you are a student checking a physics homework answer, an engineer double-checking a torque value, a traveller comparing fuel prices, or a cook scaling a recipe, the site is designed to deliver the right answer in a single click and to explain the reasoning behind it.
What we offer
The platform currently covers 14 categories of measurement and more than 300 individual units, ranging from everyday quantities such as length, mass, volume, temperature, and time to specialised domains including pressure, energy, power, force, data storage, frequency, fuel economy, and cooking measures. Every converter is available in 38 languages, so users can read formulas, examples, and explanations in their native tongue rather than translating technical content on the fly.
Each converter page follows a consistent layout designed for both quick answers and deeper learning:
- An instant input field with bidirectional conversion
- The exact formula used, written in plain notation
- A reference conversion table for common values
- A worked example showing the calculation step by step
- Short notes on the history, definition, and typical usage of each unit
Alongside the converters, AllUnits.net provides specialised tools that travellers and drivers find genuinely useful, including speed limits and toll-road information for 59 countries, and a regularly updated blog featuring original long-form content on measurement history, scientific standards, and practical guides.
Accuracy and methodology
Accuracy is not a marketing claim on this site; it is a process. All conversion factors are anchored to authoritative primary sources rather than copied from secondary aggregators. Our reference set includes the BIPM SI Brochure (which since 2019 defines the kilogram via the Planck constant and the second via the caesium-133 hyperfine transition), NIST Special Publication 811 on the use of the International System of Units, the ISO 80000 series on quantities and units, and IEC 80000-13 for digital information units such as kibibytes and mebibytes.
The editorial team verifies each factor against at least two independent authoritative sources before it is added to the database, and the database is reviewed whenever a relevant standard is revised. When official definitions change, as happened with the 2019 SI redefinition, the affected converters are updated and a note is added to the corresponding articles.
Editorial standards
Long-form content on AllUnits.net is human-written and human-reviewed. We do not publish raw, unedited output from large language models. Where AI tools are used as a research or drafting aid, the resulting text is fact-checked, rewritten, and approved by an editor before publication. Sources are cited where appropriate, and we issue corrections promptly whenever a reader reports an error or we discover one ourselves.
Performance and privacy commitments
The entire site is built as a static, pre-rendered set of pages. There is no application server processing your conversions, no user accounts, no logins, and no server-side tracking of individual visitors. Conversions happen in your browser, which means pages load quickly even on slow connections and continue to work reliably on mobile networks. Analytics are kept to the minimum needed to understand which tools are useful, and details are explained in our Privacy Policy.
Contact and corrections
AllUnits.net is maintained by a small editorial team that genuinely cares about getting the details right. If you spot a wrong factor, a confusing example, a translation issue, or a missing unit you would like to see added, please get in touch through the contact options on the site. Reader feedback has shaped many of the features now available, from additional language support to the country-specific speed-limit pages, and the project continues to evolve in the direction its users find most useful.