If you attended more than one college, your transcripts show a GPA for each school and no combined one. You can calculate it yourself with a credit-weighted average. The central application services for medical, dental and law school calculate their own version, and it can differ from yours.
The method: weight each GPA by its credits
Do not average the GPAs. Multiply each school's GPA by the credits earned there, add the results, and divide by the total credits.
Say you earned a 3.8 over 30 credits at a community college and a 3.0 over 60 credits at a university. Averaging the two GPAs gives 3.40, which is wrong. The credit-weighted answer is (3.8 × 30 + 3.0 × 60) ÷ 90, which is 3.27. The university holds two thirds of your credits, so it holds two thirds of the weight.
The transfer GPA calculator does this for any number of schools.
Convert quarter credits first
If one school used quarters, convert its credits to semester credits before you combine. A quarter hour is about two thirds of a semester hour. AADSAS states the ratio as 1.0 quarter hour to 0.667 semester hours, and LSAC multiplies quarter hours by .67.
Take a 3.6 over 45 quarter credits and a 3.2 over 60 semester credits. The quarter credits equal about 30 semester credits, so the combined GPA is 3.33. Skip the conversion and you get 3.37, because the quarter school is weighted as if it were larger than it was. The quarter system calculator converts credits for you.
How the application services calculate
Each service computes its own GPA from the coursework on your transcripts, using its own rules, which can differ from your schools' rules.
| Service | Repeated courses | Pass/fail and credit-only | Quarter credits |
|---|---|---|---|
| AMCAS (medical school) | Every attempt counts, and original grades are required even where a school replaced them. | Pass/Fail courses are reported as supplemental hours and carry no GPA weight. | Not stated in the guide chapters cited here. |
| AADSAS (dental school) | Does not recognize a school's forgiveness, academic renewal or grade replacement. Grades are taken as the transcript reports them. | Non-graded credits are left out of the GPA. | 1.0 quarter hour equals 0.667 semester hours. |
| LSAC (law school) | Repeated courses count when the transcript shows both the grade and the units. | Pass/Fail and credit-only grades are reported as credit hours outside the GPA. | Quarter hours are multiplied by .67. |
LSAC also calculates a GPA for each school and reports a cumulative GPA that covers all undergraduate work.
A retake can change the result
Your school may replace a failed grade when you retake the course. AMCAS and AADSAS ignore that replacement, and LSAC counts the repeat whenever the transcript shows both the grade and the units. Take the example from the guide to raising your GPA: a 3.00 over 45 credits that includes a 3-credit F, retaken for an A. Under replacement your school reports 3.27. Counting both attempts gives 3.06. A service that counts every attempt reports the lower figure.
Different grade-point values
LSAC converts letter grades on its own scale. An A+ is 4.33, an A is 4.00, an A- is 3.67 and a B+ is 3.33. The 4.0 scale used by the calculators on this site gives an A+ a 4.0.
Take 15 credits of A+ and 15 credits of B. On a scale where an A+ is worth 4.0, the GPA is 3.50. On LSAC's scale it is 3.67, from the same transcript.
Checking your own numbers
Calculate the combined GPA yourself to see where you stand, then expect the service's figure to differ if you have retakes, pass/fail courses or quarter credits. Use the transfer GPA calculator for the credit-weighted figure. Each service publishes its own calculator or worked examples, and those are the authority for an application.
Sources
Checked 24 September 2026. Each service revises its rules, so read the current guide for your application cycle.