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.
200k1M
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.
—$5.00
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.
—$25.00
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.
—$0.50
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.
—$5.00Amazon Bedrock
Cheapest outputLowest output rate across every provider on OpenRouter, the lab included. May come from a different provider than the cheapest input.
—$25.00Amazon Bedrock
—$2,250Anthropic 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.
34%73%
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.
72.5%96%
Overview
CompanyAnthropicAnthropic
Release dateMay 22 2025Jul 24 2026
AccessClosedClosed
Model detailsView modelView model

Frequently asked questions

Claude Opus 5 leads Claude Opus 4 on 2 of the 2 benchmarks they both report (BullshitBench v2, SWE-Bench Verified). Only Claude Opus 5 has a verified first-party API price: $5.00 per million input tokens and $25.00 per million output tokens. No pay-as-you-go API rate is tracked for Claude Opus 4. Claude Opus 4 shipped 428 days before Claude Opus 5, so benchmark comparisons should account for the intervening progress.

Context windows are 200k (Claude Opus 4) vs 1M (Claude Opus 5).

On BullshitBench v2, Claude Opus 5 leads at 73% vs Claude Opus 4 at 34%. On SWE-Bench Verified, Claude Opus 5 leads at 96% vs Claude Opus 4 at 72.5%.