Compare AI models

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.
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$1.50
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$9.00
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$0.15
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$0.75Google
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$4.50Google
$4,500Anthropic list price$750Google list price
Benchmarks
BullshitBench v2Nonsense detection — Given a confidently-worded but nonsensical prompt, does the AI spot that it makes no sense and push back — instead of playing along and inventing an answer? The score is how often it clearly called out the nonsense. Higher is better.
77%20%
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%55.1%
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%40.2%
Humanity's Last Exam · with toolsMultidisciplinary reasoning — Humanity's Last Exam — extremely hard expert questions across many subjects. “With tools” means the AI is allowed to search the web or run code while answering. Higher is better.
65.6%40.2%
ARC-AGI-2Abstract reasoning — Puzzle-style tests of abstract reasoning and pattern-finding — the kind of thing people find easy but AIs often struggle with. Higher is better.
90%72.1%
GDPval-AA v2Knowledge work — economically valuable knowledge work (v2, re-based Elo)
18531349
Overview
CompanyAnthropicGoogle
Release dateSep 1 2026May 19 2026
AccessClosedClosed
Model detailsView modelView model

Frequently asked questions

Claude Fable 5.1 leads Gemini 3.5 Flash on 6 of the 6 benchmarks they both report. Gemini 3.5 Flash is cheaper on both input and output: $1.50 vs $10.00 per million input tokens, and $9.00 vs $50.00 per million output tokens. Gemini 3.5 Flash shipped 105 days before Claude Fable 5.1, so benchmark comparisons should account for the intervening progress.

Published specifications for these two models are limited — see each model page for the latest details.

On BullshitBench v2, Claude Fable 5.1 leads at 77% vs Gemini 3.5 Flash at 20%. On SWE-Bench Pro, Claude Fable 5.1 leads at 81.2% vs Gemini 3.5 Flash at 55.1%. On Humanity's Last Exam · no tools, Claude Fable 5.1 leads at 60.9% vs Gemini 3.5 Flash at 40.2%. On Humanity's Last Exam · with tools, Claude Fable 5.1 leads at 65.6% vs Gemini 3.5 Flash at 40.2%. On ARC-AGI-2, Claude Fable 5.1 leads at 90% vs Gemini 3.5 Flash at 72.1%. On GDPval-AA v2, Claude Fable 5.1 leads at 1853 vs Gemini 3.5 Flash at 1349.