Claude 2vsClaude Mythos 5.1
Claude 2 | Claude Mythos 5.1 | |
|---|---|---|
| Specifications | ||
Context windowHow much text the model can hold in mind at once — your question, any documents you attach, the conversation so far, and its own reply. Go past it and the earliest part falls out of view. | 100k | 1M |
| BenchmarksPublished by one model only | ||
HumanEvalFunction synthesis — 164 small Python problems: the AI is given a function's description and has to write the working function. This was the coding benchmark of the GPT-3.5 and GPT-4 era, before the field moved to fixing real bugs in real repositories. Higher is better. | 71.2% | — |
Terminal-Bench 4.0Agentic terminal coding — Can the AI work in a command-line terminal — running commands and finishing technical setup tasks the way a developer would? Version 4.0 recalibrated how much time, CPU and memory each task gets, removed eight tasks and fixed nineteen, so fewer runs fail for reasons that have nothing to do with the model. Scores are not comparable with earlier versions. Higher is better. | — | 60.9% |
MMLUGeneral knowledge — A 57-subject multiple-choice exam — history, law, medicine, maths — that was the standard measure of how much a model knows from 2020 until roughly 2024, when frontier scores crowded into the high 80s and labs moved on to harder tests. The scores here were published years apart under different testing setups, so read them as a historical record rather than a like-for-like ranking. Higher is better. | 78.5% | — |
GSM8KGrade-school math — Grade-school maths word problems that take a few steps of arithmetic to work through. It separated the models of 2022 and 2023 sharply, then saturated. One caveat on the historical numbers: OpenAI included part of the GSM8K training set in GPT-4's pre-training mix, so GPT-4's score is not a clean few-shot result. Higher is better. | 88% | — |
| Overview | ||
| Company | Anthropic | Anthropic |
| Release date | Jul 11 2023 | Sep 1 2026 |
| Access | Proprietary | Proprietary |
Other comparisons
Claude 2vsGPT-6 AstraClaude Mythos 5.1vsGPT-6 AstraClaude 2vsGemini 3.8 FlashClaude Mythos 5.1vsGemini 3.8 FlashClaude 2vsMuse Spark 1.3Claude Mythos 5.1vsMuse Spark 1.3Claude 2vsGrok 4.6Claude Mythos 5.1vsGrok 4.6Claude 2vsDeepSeek-V4.1-FlashClaude Mythos 5.1vsDeepSeek-V4.1-FlashClaude 2vsMistral Medium 3.5Claude Mythos 5.1vsMistral Medium 3.5
Frequently asked questions
Claude 2 and Claude Mythos 5.1 don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Claude 2 shipped 1148 days before Claude Mythos 5.1, so benchmark comparisons should account for the intervening progress.
Context windows are 100k (Claude 2) vs 1M (Claude Mythos 5.1).
Direct benchmark comparisons are unavailable — Claude 2 and Claude Mythos 5.1 don't publish scores on any of the same benchmarks.