The PrimeGrid project provides credit for successfully completing work, and tracks credit by each subproject.
PrimeGrid also provides badges and shields as evidence of work completed by participants. The amount of PrimeGrid Credit for a specific project or subproject determines the appropriate badge or shield for that project. All manual sieving and PRPNet Credit counts toward a PSA badge. All PrimeGrid Credit for GFN projects counts toward a GFN badge. All Proth LLR tasks (PPSE, PPS, and MEGA) count toward a PPS badge. All other applications have their own individual badges.
Badges are ranked by color, and at 100 million credits, the badge color resets, but the shape changes to a shield (sometimes referred to as a "double" badge). PrimeGrid Credit required for a particilar badge is as follows:
Some users have achieved a "Full Set" of all available subprojects. PrimeGrid users are encouraged to announce this achievement at: http://www.primegrid.com/forum_thread.php?id=1482
As of this writing (17 July 2016), the highest badge awarded is a ruby shield.
Past projects for which some PrimeGrid users have badges are:
- 321 Sieve
- Arithmetic Progression of 26 primes
- Prime Sierpinski Problem/Seventeen or Bust Sieve
- Twin Prime search
- ESP Sieve