A hydrometer helps you track fermentation by measuring a liquid’s density (specific gravity). In homebrewing, this can indicate sugar levels before and after fermentation and provide an estimate of potential alcohol by volume (ABV).

• Triple-scale hydrometers commonly show specific gravity, Brix, and potential ABV for beer, wine, and cider.
• To use, gently float it in a sample taken in a tall test jar and read at eye level.
• Temperature affects readings, so check your hydrometer’s calibration temperature and apply corrections if needed.
• Handle glass parts carefully and clean after use. You’ll find hydrometers, test jars, and accessories here to build a simple testing setup.

They measure different things:

• Hygrometer: Measures humidity in the air. It’s for tracking moisture levels, not liquids.
• Hydrometer: Measures the density of liquids. This page features hydrometers for beverages and other uses.

Common types here include:

• Triple-scale hydrometers for beer, wine, and cider (specific gravity, Brix, potential ABV).
• Proof & Tralle meters for distilled spirits (proof and % alcohol readings).
• Specialty options like syrup or process-specific hydrometers.

Choose based on your liquid: fermentation batches use triple-scale; clear, sugar-free spirits use proof & tralle. Always check the calibration temperature and handling instructions.

1. Prepare a sample: Fill a tall, narrow test jar with enough liquid for the hydrometer to float freely.
2. Insert carefully: Lower the hydrometer gently and spin it slightly to shed bubbles.
3. Read at eye level: Note the value at the bottom of the meniscus on the correct scale (specific gravity, Brix, or potential ABV).
4. Consider temperature: Compare your sample temperature to the hydrometer’s calibration temperature and apply corrections if your instructions call for it.
5. Record and compare: Track starting and finishing readings to estimate fermentation progress.

Rinse and dry your tools after use. Small technique tweaks—like removing foam and avoiding contact with the jar walls—can improve consistency.

A proof & tralle hydrometer is designed for clear, sugar-free distilled spirits. It typically reads two scales—proof and % alcohol—so it’s suited for spirits testing rather than beer, wine, or liqueurs that contain sugar.

• Use it after distillation or blending to gauge alcohol strength in spirit samples.
• Always take readings in a tall test cylinder and review the meter’s temperature calibration; temperature adjustments may be necessary.
• Handle glass carefully and follow all applicable laws and safety guidelines when working with spirits.

If you’re testing fermenting beverages, a triple-scale hydrometer is usually the more appropriate choice.

Choose a tall, narrow cylinder that lets your hydrometer float freely without touching the sides or bottom.

• Height: Many beverage hydrometers work well with jars around 10–12 inches tall, as seen in options on this page.
• Capacity: Common choices include ~100 mL and ~250 mL cylinders; pick a size that accommodates the length of your hydrometer while minimizing sample volume.
• Material: Borosilicate glass offers clarity; plastic can be more impact-resistant. Either can work when used properly.

Confirm your hydrometer’s length and diameter, then match a jar that provides clearance and stable float for easier, more consistent readings.