Compare AI models

Specifications
ParametersA rough measure of how big the model is. More parameters usually means more capable and more expensive to run, though it is a poor guide on its own — a smaller, newer model often beats a larger, older one.
—30B
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.
1M—
API pricingUSD per 1M tokens · lower wins
Input priceWhat you pay for everything you send the model — your question, plus any documents or earlier conversation you include with it.
$10.00—
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.
$50.00—
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.
$0.25—
Cheapest inputLowest input rate across every provider on OpenRouter, the lab included. The cheapest endpoint may run a quantised build or a shorter context — see "Available from" on the model page.
$10.00Amazon Bedrock$0.30DeepInfra
Cheapest outputLowest output rate across every provider on OpenRouter, the lab included. May come from a different provider than the cheapest input.
$50.00Amazon Bedrock$1.20DeepInfra
$4,500Anthropic list price$120DeepInfra · bf16
Benchmarks
SWE-Bench ProAgentic coding — Can the AI fix real bugs in real software? It's handed actual problems from open-source projects and has to write code that genuinely solves them. Higher is better.
81.2%51.2%
Humanity's Last Exam · no toolsMultidisciplinary reasoning — Humanity's Last Exam — extremely hard expert questions across many subjects, written so you can't just look up the answer. “No tools” means the AI answers on its own. Higher is better.
60.9%22%
GDPval-AA v2Knowledge work — economically valuable knowledge work (v2, re-based Elo)
1853953
Overview
CompanyAnthropicMeta
Release dateSep 1 2026Aug 10 2026
AccessClosedOpen Weight
Model detailsView modelView model

Frequently asked questions

Claude Fable 5.1 leads Muse Glimmer on 3 of the 3 benchmarks they both report (SWE-Bench Pro, Humanity's Last Exam, GDPval-AA v2). Only Claude Fable 5.1 has a verified first-party API price: $10.00 per million input tokens and $50.00 per million output tokens. No pay-as-you-go API rate is tracked for Muse Glimmer. Muse Glimmer shipped 22 days before Claude Fable 5.1, so benchmark comparisons should account for the intervening progress.

Claude Fable 5.1 is closed, while Muse Glimmer is open weight.

On SWE-Bench Pro, Claude Fable 5.1 leads at 81.2% vs Muse Glimmer at 51.2%. On Humanity's Last Exam · no tools, Claude Fable 5.1 leads at 60.9% vs Muse Glimmer at 22%. On GDPval-AA v2, Claude Fable 5.1 leads at 1853 vs Muse Glimmer at 953.