Grade Decay Calculator

Your GPA so far.

Total credits completed.

Grade point of the bad course (e.g., C = 2.0).

Credit hours of the old course.

Credits you plan to take (to dilute decay).

GPA needed to reach.

Grade Decay Calculator: Full Guide (2025)

Use our grade decay calculator to see how old bad grades affect your GPA over time. Plan retakes, new courses, and recovery strategies.

What is Grade Decay?

A low grade from years ago continues to pull down your cumulative GPA as you earn more credits. The impact decreases slowly.

Decay Formula

Current GPA = (Total Grade Points) / (Total Credits)

Impact of Old Grade = (Old Grade × Old Credits) / Total Credits

Example

ScenarioCreditsGPAOld C Impact
After 15 credits153.00.40 pull-down
After 60 credits603.50.10 pull-down
After 120 credits1203.70.05 pull-down

Retake & Replacement

Recovery Strategies

  1. Take more credits at high GPA
  2. Retake course (if allowed)
  3. Focus on major GPA

Step-by-Step Guide

  1. Enter current GPA & credits
  2. Add old low grade
  3. Plan future credits
  4. See decay & recovery

Why Use This Calculator?

  • Decay impact
  • Recovery plan
  • Retake simulation
  • Free & instant

FAQ

Does a C from freshman year hurt?

Yes, but less after 100+ credits.

Can I remove old grades?

Rarely. Use forgiveness or retake policies.

How many credits to dilute a 2.0?

~90 more at 4.0 to reduce impact to 0.05.

Pro Tips

  • Track major GPA separately
  • Use GPA Boost for honors
  • Apply early before decay hurts

Conclusion

Don’t let old grades haunt your future. Use our grade decay calculator to plan recovery. Calculate now!

Related: Grade Replacement | GPA Boost