How we convert

A converter is only as good as the numbers behind it. This page explains where ours come from, how we round them and what we do when we cannot find an official figure.

Where the numbers come from

• Unit definitions come from NIST’s published conversion factors (Special Publication 811, Appendix B.8, and its notes on the international foot and acre). NIST marks some factors as exact; the others are NIST’s rounded seven-figure values, and we use them as published.
• Kitchen weights come from USDA FoodData Central, which is in the public domain. Each staple links to the USDA record we used.
• Gold hallmarking facts come from the Bureau of Indian Standards’ hallmarking pages. The tola uses the conversion rate in the Standards of Weights and Measures Act, 1956.
• Local land units come from state revenue and land-records departments and state laws. So far we have verified Haryana’s published units, the Tamil Nadu ground, the Bihar decimal, and the cent and guntha as fractions of the acre (from the Tamil Nadu survey department and Maharashtra’s land-records department).

When there is no official figure

We leave it out and say so. That is why the kitchen converter has no poha or jaggery powder, why the gold converter asks for your jeweller’s ratti value instead of assuming one, and why most state land units, such as the bigha, marla and katha outside the states listed on the land page, are marked “not verified; check with your local revenue office”. We would rather show a gap than a number we cannot stand behind.

Rounding

• Kitchen weights are shown to the nearest gram from 10 g up, to one decimal from 0.1 g, and to two decimals below that. Cup and spoon counts are shown to two decimals.
• Other results are shown to six significant figures with Indian digit grouping. Results of 1,00,000 or more are shown in full, to at most two decimal places, so a whole number is never rounded off. Calculations use the full factor; only the display is rounded.

Review dates

Every converter page shows when its values were last checked (26 October 2026) and when the next review is due (26 October 2027). If you open a page after that date, a notice appears asking you to check the sources, so a stale table cannot pass silently as current.

How the content is made

Researched and drafted with AI assistance, checked against the sources cited on each page; publisher review recorded in our corrections log. We do not test products and we do not claim specialist credentials.

Found an error?

Please tell us, with the page, the value and the source you are relying on. We check every report against the source and record corrections in the log on the contact page.