Albumin/Globulin (A/G) Ratio Calculator

How it is calculated

Blood tests report albumin and total protein but not globulin, so the tool derives it: Globulin = TP − Alb and A/G ratio = Alb / Globulin. Alb is serum albumin and TP is total protein, both in g/dL. The ratio is shown with two decimals and globulin in g/dL with one decimal. The tool gives no result when albumin is zero or negative, when total protein is equal to or smaller than albumin (globulin would be zero or negative), or when the values are implausible for g/dL: albumin above 10 or total protein above 20. It does not convert units and does not label the ratio as low or normal.

Common mistakes

• Entering values in g/L (42 and 70). The tool expects g/dL and gives no result because 42 is far above the accepted albumin limit of 10; divide g/L values by 10 first.
• Typing globulin in the total protein field. Total protein must be larger than albumin, so a small globulin value gives no result.
• Swapping albumin and total protein. If albumin is larger than total protein, or the two are equal, globulin would be zero or negative and nothing is shown.
• Using values that are almost equal. With albumin 4.2 and total protein 4.21, globulin rounds to 0.0 g/dL and the ratio jumps to 420.00, which is a rounding artefact, not a finding.
• Judging the ratio on its own. A low or high ratio does not say whether albumin or globulin is the cause, so look at both numbers and discuss them with a clinician.