Contact
Last updated: September 9, 2026
One address reaches the Milli to Micro editorial team. Corrections to a published figure are the priority — if something on this site is wrong, telling us is the most useful thing you can do with this page.
What to include
We read everything, and a message that pins down the exact page and the exact number gets acted on far faster than one that does not. Pick whichever of these fits and put it in the subject line.
A number on the site is wrong
This is the one we most want to hear about, and it goes to the front of the queue. Include the page URL, the exact figure or sentence, and what it should say. If you have a standards reference — an SI Brochure table, a NIST section, an ISO 80000 clause, or a manufacturer datasheet — include it and the fix will be quicker.
Email with subject “Correction” →A unit pair is missing
Tell us the two units and, more usefully, the situation you needed it for. We add pairs where there is a real use case and a sourceable definition, not to pad the site out — so the context matters more than the request itself.
Email with subject “Unit request” →The calculator behaved oddly
Include the exact value you typed, what it returned, what you expected, and your browser. Rounding artefacts are the interesting case: the converter shifts decimal exponents rather than multiplying in binary floating point, so if you have found a value that comes back with a trailing 999 or a stray digit, that is a genuine bug and we want it.
Email with subject “Bug report” →Reuse, citation, or press
Conversion factors themselves are facts from the SI standards and belong to nobody — use them freely. For reproducing our explanatory text, tables, or charts, or for questions about the site itself, get in touch and say what you have in mind.
Email with subject “Permissions” →Before you write
A few things are already answered elsewhere: how we source and correct figures, who maintains the site, and the full SI prefix table with its BIPM and NIST references. The converter runs entirely in your browser and sends nothing you type to a server, which is also why we cannot look up what you entered — if you are reporting a calculation problem, include the value.
We cannot advise on medical dosing, radiation safety, or any decision where a converted figure would be acted on directly. The arithmetic here is exact, but it is not a substitute for the protocol, the datasheet, or the person responsible for the measurement.