Hydrometer Correction Calculator

How It Works

Hydrometers measure density by how deep they float in liquid. They are calibrated at a specific temperature (usually 60F or 68F, check your hydrometer). Warmer liquid is less dense, so the hydrometer sinks deeper and reads lower than the true gravity. Cooler liquid is denser, making the hydrometer read higher. The correction is small but meaningful — at 80F with a 60F calibration, the correction is about +0.001, which equates to roughly 0.13% ABV difference. For the most accurate readings, cool your sample close to calibration temperature, or always apply this correction. Never put a hydrometer in hot wort — it is inaccurate above 100F and the glass can crack.