Plato to Gravity Calculator
Convert between degrees Plato and specific gravity, in both directions.
How it works
This is a two-way converter. Type a Plato (or Brix) value to get the equivalent specific gravity, or type a specific gravity to get the equivalent Plato. Both readouts update as you type. Degrees Plato measures dissolved solids by weight; specific gravity measures density - they describe the same wort two different ways.
SG = 1 + P / (258.6 − (P/258.2) × 227.1)
Plato ≈ Brix for brewing purposes.
Sources: Plato/Brix cubic relationship as documented by Brewer's Friend.
Refractometers read in Brix and assume a sucrose solution. Once alcohol is present (during or after fermentation) a refractometer reading needs a separate correction - this converter is for unfermented wort.
Frequently asked questions
- Is degrees Plato the same as Brix?
- For practical brewing they are interchangeable. Both measure dissolved sucrose-equivalent solids by weight, and the two scales agree to within a few hundredths of a degree across normal wort gravities. A refractometer reads in Brix; a saccharometer reads in Plato.
- How do I convert Plato to specific gravity?
- Use
SG = 1 + P / (258.6 − (P/258.2) × 227.1). As a rough rule of thumb, multiply the Plato value by 4 to get the last two gravity points - 12.5 °P is about 1.050. - Why do gravity points stop tracking Plato at high strength?
- The relationship is not perfectly linear. The "× 4" shortcut drifts at high gravity, so for strong worts use the full cubic conversion this calculator applies rather than the mental approximation.