In general, a hydrometer is an instrument which is more commonly used for testing the density of a liquid in relation to water. This means that it is used in many different sectors and industries as well as being a popular instrument that can be used in the home.

Hydrometer Uses

One of the most popular reasons for people needing to use a hydrometer is to test alcohol content when brewing alcohol. This can be for both wine and beer manufacturers or simply by the home brewer trying to produce alcohol themselves! The Hydrometer is a much needed tool for the home brewer which enables them to monitor the correct levels of sugar in the mixture which results in making the task much easier.

Please find below a wide range of Hydrometers below for all kinds of applications.



Thermometer | Pressure Gauge | Hydrometer | Large Quantities & Special Orders

Other designs and specifications are available from our thermometer, pressure gauge and hydrometer range to special order. Most products can be branded and packed to your specifications. Minimum quantities apply. Tell us what you need by filling out our contact form

Trading is subject to our Standard Terms & Conditions

Hydrometer Information

General Purpose Specific Gravity Hydrometers

The specific gravity 60/60°F scale compares the relative density of a given liquid with that of water, at 60°F (15.6°C). The instruments listed are similar to hydrometers included in ISO 650 and in the (now superseded) 1960 issue of British Standard 718.
Two of the ‘series’ of hydrometers are listed below and a further series is on the next page with some wider range types.


Twaddle Hydrometers 

The Twaddle scale is a simplified scale based on specific gravity where 0° Twaddle equates to SG60/60°F of 1.00 (that of water) and each degree Twaddle equals 0.005°SG. These hydrometers are available in 2 lengths each with single degree divisions and are adjusted for use at 15.6°C (60°F) for medium surface tension liquids.


Baumé Hydrometers

The Baumé hydrometers listed are for liquids heavier than water. Zero degrees Baumé equates to an SG 60/60°F of 1.00. The instruments are all 250mm long and are adjusted at 15.6°C (60°F) and suitable for medium surface tension liquids.


BS 718 : 1991 Density Hydrometers

BS 718 : 1991 is generally aligned with ISO 387 and ISO 649. The specification includes five series and three sub-series of Hydrometers, of which the most widely used are listed. They are calibrated using the accepted units of grams per millilitre (g/ml) and are adjusted except for the “SP” sub-series at 20°C.


ASTM E 100 Hydrometers

The American Society for Testing and Materials (ASTM) Specification E 100 describes hydrometers using the API (American Petroleum Institute) scale and others in degrees Specific Gravity.
330mm Long Plain Hydrometers adjusted at 60°F for Petroleum Products and other liquids of low surface tension.


Brix Hydrometers

Measuring the percentage of sugar and commonly used in wine production. The Brix scale is the equivalent to Balling and Plato scales. Adjusted at 15.6°C (60°F) for a surface tension 55mN/m.


Wine & Beer Hydrometer

Measuring the specific gravity of wine and beer and designed for home use. This hydrometer will monitor the fermentation process and allows the percentage alcohol to be determined easily with a zoned scale. Adjusted at 20°C.