Compare AI models

Specifications
Context windowHow much information the model can work with in one request, measured in tokens — pieces of words or other data. This includes your question, attachments, conversation and reply. Limits can vary by model variant and provider.
1M128k
Benchmarks
SWE-Bench VerifiedCoding — Real coding tasks pulled from open-source projects — the AI has to find and fix actual bugs. A human-checked version of the original SWE-Bench. Higher is better.
93.9%38%
GPQA DiamondScience — Graduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better.
94.5%69.5%
Overview
CompanyAnthropicOpenAI
Release dateApr 7 2026Feb 27 2025
AccessClosedClosed
Model detailsView modelView model

Frequently asked questions

Claude Mythos Preview leads GPT-4.5 on 2 of the 2 benchmarks they both report (SWE-Bench Verified, GPQA Diamond). GPT-4.5 shipped 404 days before Claude Mythos Preview, so benchmark comparisons should account for the intervening progress.

Context windows are 1M (Claude Mythos Preview) vs 128k (GPT-4.5).

On SWE-Bench Verified, Claude Mythos Preview leads at 93.9% vs GPT-4.5 at 38%. On GPQA Diamond, Claude Mythos Preview leads at 94.5% vs GPT-4.5 at 69.5%.