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.
1M1.05M
API pricingUSD per 1M tokens · lower wins · base tier
Input priceWhat you pay for everything you send the model — your question, plus any documents or earlier conversation you include with it.
—$1.00
Output priceWhat you pay for the text the model writes back. It is normally the dearer half: producing an answer costs more than reading one.
—$5.00
Cached input priceA reduced rate for text you send over and over. If every request starts with the same instructions or the same document, the provider keeps a copy ready and charges less to read it again.
—$0.05
—$450OpenAI list price
Benchmarks
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%50.3%
Overview
CompanyAnthropicOpenAI
Release dateSep 1 2026Oct 26 2026
AccessClosedClosed
Model detailsView modelView model

Frequently asked questions

Claude Mythos 5.1 leads GPT-6.1 Terra on 1 of the 1 benchmark they both report (Terminal-Bench 4.0). Only GPT-6.1 Terra has a verified first-party API price: $1.00 per million input tokens and $5.00 per million output tokens. No pay-as-you-go API rate is tracked for Claude Mythos 5.1. Claude Mythos 5.1 shipped 55 days before GPT-6.1 Terra, so benchmark comparisons should account for the intervening progress.

Context windows are 1M (Claude Mythos 5.1) vs 1.05M (GPT-6.1 Terra).

On Terminal-Bench 4.0, Claude Mythos 5.1 leads at 60.9% vs GPT-6.1 Terra at 50.3%.