Hydrometers & Refractometers

Hydrometers and Refractometers for Fermentation Gravity Testing

Hydrometers and refractometers help brewers and fermentation makers measure gravity, estimate fermentable sugar, track fermentation progress, and make better decisions before packaging. Gravity readings are useful for beer, wine, cider, mead, sake, hard seltzer, kombucha, and many other small-batch beverages.

Hydrometers measure density in a sample, while refractometers use a small sample to estimate sugar concentration. Each tool has its own strengths and correction needs, especially once alcohol is present. Use the product instructions and a consistent sampling method so readings are meaningful from batch to batch.

Common gravity testing uses

• Original gravity: check the starting strength of wort, must, juice, or other fermentable bases.
• Fermentation progress: compare readings over time to see whether gravity is still changing.
• Final gravity: confirm stability before packaging, backsweetening, or conditioning.
• Recipe records: use consistent readings to improve repeat batches and troubleshooting.

For related tools, browse pH measurement tools, ABV calculator, keg carbonation calculator, and brewing equipment.