Standard Reference Method (SRM)

We, as humans, are very visual. We use this sense to give us quick feedback on many aspects of life. Brewers only have one chance to set the first impression of a beer as it pours into our glass. Based on the style of the beer, the color is the first gauge for what we expect in a beer. Other factors like retention, lacing, and color of the foam play a big part also.

SRM is a scale for measuring the color intensity of a beer (it's more technical than this, but we will leave it there). SRM was adopted by the Ameican Society of Brewing Chemists in 1951. There is another, older scale named degrees Lovibond (devised by Joseph Williams Lovibond) that the SRM scale has replaced.

The color chart and colors below are an approximation of the actual colors in the SRM scale. Two Beer Dudes tries to use these color descriptions or SRM number when rating beer. We hope that you will do the same so that everyone is on a level playing field while describing our beer experience. Enjoy!

Beer Colors and SRM Value
Color Swatch SRM Color
 
2 Pale Straw
 
3 Straw
 
4 Pale Gold
 
6 Deep Gold
 
9 Pale Amber
 
12 Medium Amber
 
15 Deep Amber
 
18 Amber-Brown
 
20 Brown
 
24 Ruby Brown
 
30 Deep Brown
 
40 Black
Beer Style SRM Color Ranges
Style SRM Range
Pilsner 2 - 7
Witbier, Berliner Weisse 2 - 4
Belgian Strong Ale 4 - 7
Maibock 4 - 10
Vienna Lager 7 - 14
Oktoberfest 4 - 12
American Pale Ale 6 - 14
Pale Ale 5 - 14
English Golden Ale 4 - 8
Bavarian Weizen 4 - 10
Bitter, ESB 8 - 14
Märzen 7 - 15
Imperial Pale Ale 5 - 11
Bière de Garde 6 - 13
Dunkel Weizen 9 - 13
Amber Ale 11 - 18
English Brown Ale 12 - 22
Bock 15 - 30
Porter 20 - 40
Oatmeal Stout 25 - 40
Baltic Porter 17 - 40
Foreign Stout 30 - 65
Imperial Stout 50 - 80
Source: Tasting Beer by Randy Mosher
Morey Equation
  • This equation is typically used in beer software to approximate color.
  • SRM = 1.4922 * (MCU ^ 0.68590)
  • good for color < 50 SRM
  • MCU = grainColor * grainWeightLBS / volumeGallons
degress Lovibond
  • Was the first scale to officially and uniformily measure the the color of beer in the 1860s.
  • A sample of the beer was placed in a "Tintometer" and compared with several glass slides.
  • The color disc that most closely represented the beer was than assigned to the beer.
European Brewing Convention
  • Another measurement of color for beer. The scale is approximately double the SRM scale.