EC ↔ ppm Converter
Convert between electrical conductivity (EC) and total dissolved solids (ppm/TDS). Because ppm depends on your meter's conversion scale, pick the right one first.
The 500 scale is standard in North America (e.g. Hanna, most US hobby TDS pens). Check your meter's manual if unsure.
mS/cm
= 1500 µS/cm
TDS (ppm, ×500)
750ppm
ppm is not a direct measurement — meters compute it from EC using a fixed factor that varies by brand and region. When comparing recipes or meters, always confirm which scale each one uses.
Embed this tool on your site
Free to use. Paste this into any page — it stays in sync with the settings you picked above.
How it works
EC (mS/cm) is what a meter actually measures; ppm is EC multiplied by a scale factor.
- 1Select the conversion scale your meter uses: 500 (NaCl, common in the US), 640 (Europe), or 700 (KCl, common in Australia).
- 2Choose a direction — EC to ppm, or ppm to EC.
- 3Enter your value. The result updates instantly, with the equivalent in µS/cm shown as well.
- 4Formula: ppm = EC(mS/cm) × factor. For example, 1.5 mS/cm on the 500 scale is 750 ppm.