Model comparison
Claude Opus 5.5 vs Claude Sonnet 5 (Free)
Price history, scores and specs for both models, line by line. Every value shows where it came from and when we last confirmed it.
Anthropic
Claude Opus 5.5
Claude Opus 5.5 is Anthropic's flagship model for demanding reasoning, coding, and long-horizon agentic work, succeeding Claude Opus 5.
Anthropic
Claude Sonnet 5 (Free)
Everyday Claude agent model for coding, planning, browsing, and general work.
Price history
Prices side by side, day by day
- Claude Opus 5.5
- Claude Sonnet 5 (Free) No price history checked yet
- Claude Opus 5.5
- Claude Sonnet 5 (Free) No price history checked yet
Prices are the listed OpenRouter base rates in US dollars. A day we could not confirm is left out of the line, never filled in.
Price
What each one costs now
| Measure | Claude Opus 5.5 | Claude Sonnet 5 (Free) |
|---|---|---|
| Input price | $4.00 per million tokens | Not checked yet |
| Output price | $20.00 per million tokens | Not checked yet |
Scores
Benchmarks, with source and date
| Measure | Claude Opus 5.5 | Claude Sonnet 5 (Free) |
|---|---|---|
| Artificial Analysis Intelligence Index | 59.1 | Not checked yet |
| LMArena text rating (Elo) | 1,513 | Not checked yet |
| LMArena web development rating (Elo) | 1,814 | Not checked yet |
| LMArena vision rating (Elo) | 1,324 | Not checked yet |
| Design Arena rating (Elo) | 1,461 | Not checked yet |
Specs
Context, modalities and tool use
| Measure | Claude Opus 5.5 | Claude Sonnet 5 (Free) |
|---|---|---|
| Context window | 1,000,000 tokens | Not checked yet |
| Reads | Text, Images, Files | Not checked yet |
| Writes | Text | Not checked yet |
| Tool calling | Yes | Not checked yet |
| Reasoning mode | Yes | Not checked yet |
| Open weights | No | Not checked yet |
| Listed since | 22 Sept 2026 | Not checked yet |
Usage
How much each one is used
| Measure | Claude Opus 5.5 | Claude Sonnet 5 (Free) |
|---|---|---|
| Tokens served on OpenRouter in a day | 1.1T (for 10 Nov 2026) | Not checked yet |
| Requests on OpenRouter in a day | 9.4M (for 10 Nov 2026) | Not checked yet |
| Tool calls on OpenRouter in a day | 5.7M (for 10 Nov 2026) | Not checked yet |
| Token usage, last 7 days | Up 1% on the week before (for 10 Nov 2026) | Not checked yet |
- Claude Opus 5.5
- Claude Sonnet 5 (Free) No usage checked yet
How this works
One link, either order
This link stays the same whichever order you name the two models in, so you can share it as it is. A line appears only when at least one model has a value we confirmed from a source; values we have not confirmed are left out, never guessed. To add a third record of any type, use the open comparison. Read how we check facts.