Head-to-head comparison across 3 benchmark categories
Claude Mythos Preview
84
GLM-5.1
77
Pick Claude Mythos Preview if you want the stronger benchmark profile. GLM-5.1 only becomes the better choice if you want the cheaper token bill.
Agentic
+15.7 difference
Coding
+25.4 difference
Knowledge
+22.6 difference
Claude Mythos Preview
GLM-5.1
$25 / $125
$1.4 / $4.4
N/A
N/A
N/A
N/A
1M
203K
Pick Claude Mythos Preview if you want the stronger benchmark profile. GLM-5.1 only becomes the better choice if you want the cheaper token bill.
Claude Mythos Preview is clearly ahead on the aggregate, 84 to 77. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
Claude Mythos Preview's sharpest advantage is in coding, where it averages 83.8 against 58.4. The single biggest benchmark swing on the page is SWE-bench Pro, 77.8% to 58.4%.
Claude Mythos Preview is also the more expensive model on tokens at $25.00 input / $125.00 output per 1M tokens, versus $1.40 input / $4.40 output per 1M tokens for GLM-5.1. That is roughly 28.4x on output cost alone. Claude Mythos Preview gives you the larger context window at 1M, compared with 203K for GLM-5.1.
Claude Mythos Preview is ahead overall, 84 to 77. The biggest single separator in this matchup is SWE-bench Pro, where the scores are 77.8% and 58.4%.
Claude Mythos Preview has the edge for knowledge tasks in this comparison, averaging 74.9 versus 52.3. Inside this category, HLE is the benchmark that creates the most daylight between them.
Claude Mythos Preview has the edge for coding in this comparison, averaging 83.8 versus 58.4. Inside this category, SWE-bench Pro is the benchmark that creates the most daylight between them.
Claude Mythos Preview has the edge for agentic tasks in this comparison, averaging 80.9 versus 65.2. Inside this category, Terminal-Bench 2.0 is the benchmark that creates the most daylight between them.
Get notified when new models drop, benchmark scores change, or the leaderboard shifts. One email per week.
Free. No spam. Unsubscribe anytime. We only store derived location metadata for consent routing.