About this tool
Convert therms to British thermal units instantly. Free, bidirectional, and fully in-browser.
1 therm equals 99976.12898 British thermal units — enter any therm value to convert it to British thermal units instantly. This Therm to British thermal unit converter is a client-side tool: it applies a single multiplication (BTU = thm × 99976.12898) in your browser, updates the moment you type, and works in both directions — edit either field, or press swap, to convert British thermal units back to therms. A reference table lists common therm values already converted, and nothing you enter is sent to a server.
Open Therm to British thermal unit Converter on AltFTool — it loads instantly in your browser.
Type the value you want to convert into the Therm field.
Read the equivalent in British thermal units in the result field, and copy it if needed.
Use the decimal-places slider for more or less precision, or press swap to convert British thermal units to therms.
The result updates as you type, and the swap button flips the conversion to british thermal unit → therm without reloading.
The conversion uses the precise factor (BTU = thm × 99976.12898), so the number matches a manual calculation to the decimal places you choose.
A slider sets 0–10 decimal places, and very small or very large results switch to scientific notation instead of rounding to zero.
Everything runs locally in your browser — no upload, no account, no limit on conversions.
One therm is 99976.12898 British thermal units. Multiply the therm value by 99976.12898 to convert. For example, 10 thm = 999761.2898 BTU.
BTU = thm × 99976.12898. This tool applies it automatically and shows a worked example: 10 thm = 999761.2898 BTU.
Yes. Press the swap button, or type into the british thermal unit field, and the tool converts British thermal units to therms using the inverse of the same relationship.
It uses the standard energy and work definition (BTU = thm × 99976.12898), not a rounded approximation, so results are exact to the number of decimal places you select.
Yes. The converter is a browser-side script with no network calls: your values are never uploaded, and once the page has loaded it keeps working without a connection.
Add the Therm to British thermal unit Converter widget to your blog or website — free, responsive, no signup. Just keep the “Widget by AltFTool” credit link visible.
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