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Parts per Trillion to Parts per Million Conversion

Enter an amount in parts per trillion and press Convert to see that same amount written in parts per million. One part per trillion is 1/1,000,000 of a part per million, so every ppt value is divided by 1,000,000.

About the ppt to ppm conversion

Parts per million (ppm) and parts per trillion (ppt) are two ways of writing a very small share of a whole. A part per million is one part in 10^6, that is 1/1,000,000, while a part per trillion is one part in 10^12, that is 1/1,000,000,000,000, so the trillion part is by far the smaller share.

A trillion is one million times a million, and that is what links the two units: 1 ppm equals 1,000,000 ppt. The same quantity therefore reads as a much larger number in ppt than in ppm, and rewriting it in ppm takes a single division by 1,000,000.

ppt to ppm formula

The amount in parts per million, x(ppm), equals the amount in parts per trillion, x(ppt), divided by 1,000,000: x(ppm) = x(ppt) / 1,000,000.

For example, 7000 parts per trillion works out as 7000 / 1,000,000 = 0.007 ppm, and 1 ppt reads as 0.000001 ppm. To go the other way, from ppm back to ppt, multiply by 1,000,000 instead.