Calculators
Salinity

Salinity & specific gravity converter

Convert between salinity (ppt) and specific gravity near reef salinity. The reef target is 34–36 ppt (specific gravity 1.025–1.027) at 25 °C / 77 °F.

Reef target
Target band: 34–36 ppt · specific gravity 1.025–1.027, measured at 25 °C / 77 °F.
Source: reef target and ppt↔specific-gravity anchors from published reef chemistry (Holmes-Farley). Linear near reef salinity — a refractometer calibrated at the reference temperature is the authority.

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