Skip to the comparison
STET
Run it on your repo

GPT 5.6 Luna max vs GPT 6 Sol medium

GPT 6 Sol medium leads on speed; GPT 5.6 Luna max on cost; quality is too close to call.

Quality
+3.3 pts
GPT 6 Sol medium
2–1 head to head, 21 tied
Speed
1.8× faster
GPT 6 Sol medium
15.4 min vs 28.5 min per task
Cost
3.3× cheaper
GPT 5.6 Luna max
$0.90 vs $3.01 per task

24 tasksData from

Stet score

GPT 5.6 Luna maxmax reasoningRank 9 of 17

49.995% range 44.5–55.6

GPT 6 Sol mediummedium reasoningRank 5 of 17

53.295% range 49.0–57.93.3 points higher

A directional read: their 95% score ranges overlap.

Quality

Head-to-head matchups

GPT 5.6 Luna max won1

Tied21

GPT 6 Sol medium won2

GPT 6 Sol medium’s win share 52%, 95% range 46–59%Ties are within judge noise.

Task by task

GPT 5.6 Luna max solved 0 tasks that GPT 6 Sol medium didn’t, and GPT 6 Sol medium solved 2 that GPT 5.6 Luna max didn’t. Both solved 10; neither solved 12.

stet-commit-f8ae1177Solved by 9 of 17 setups

  • GPT 5.6 Luna maxFailed
  • GPT 6 Sol mediumPassed tests

A task counts as solved when its tests passed or a judge found the fix equivalent to the merged change, as in the leaderboard’s Solved column. Stet score also weighs code quality, so it can order the two differently.

All 24 compared tasks
Task by task
TaskGPT 5.6 Luna maxGPT 6 Sol mediumSolved by
stet-232b50baPassed testsPassed testsBoth
stet-3169aefaPassed testsPassed testsBoth
stet-5276aa3fPassed testsPassed testsBoth
stet-89dfbc27Passed testsPassed testsBoth
stet-b28f4fe7Passed testsPassed testsBoth
stet-commit-bbbbae09Passed testsPassed testsBoth
stet-66762b4cEquivalent to the merged fixPassed testsBoth
stet-commit-5d766ddeEquivalent to the merged fixEquivalent to the merged fixBoth
stet-commit-f0caded9Equivalent to the merged fixEquivalent to the merged fixBoth
stet-43493c52Passed testsPassed testsBoth
stet-commit-f8ae1177FailedPassed testsGPT 6 Sol medium only
stet-15439c21FailedFailedNeither
stet-2450ca2dFailedFailedNeither
stet-commit-342d0ac0FailedEquivalent to the merged fixGPT 6 Sol medium only
stet-6f84e978FailedFailedNeither
stet-commit-60a0e6c2FailedFailedNeither
stet-commit-5e075641FailedFailedNeither
stet-commit-2826765eFailedFailedNeither
stet-commit-a8716b88FailedFailedNeither
stet-commit-e928166fFailedFailedNeither
stet-commit-30506f8eFailedFailedNeither
stet-commit-87814583FailedFailedNeither
stet-commit-d2ab0c25FailedFailedNeither
stet-commit-e41c2e2dFailedFailedNeither

Side by side

Side by side
MetricGPT 5.6 Luna maxGPT 6 Sol medium
Reasoning effortmaxmedium
Rank9 of 175 of 17
Stet score49.995% range 44.5–55.653.295% range 49.0–57.9
Solved10/247 passed, 3 judged equivalent12/249 passed, 3 judged equivalent
Cost / task$0.90$3.01
Agent time / task28.5 min15.4 min

See which setup wins on your repo

Stet replays your merged PRs, scores quality above pass/fail, and delivers comparison reports through your agent.

Run it on your repo

About this data

  • 24 tasks, each a merged change replayed from the repo as it was just before the merge.
  • Data from .
  • Both setups come from the same leaderboard run of 17 setups: bmk_d4ba310fdf50db4ccb2092e3.

See all 17 setups on the leaderboardHow Stet measures