Mistral Large 4 vs Claude Opus 5.5
Facts only. This page does not pick a winner. For a picked winner, see the use case comparison on Tools.
| Mistral Large 4 | Claude Opus 5.5 | |
|---|---|---|
| API model IDs | mistral-large-4, mistral-large-4-0 | claude-opus-5-5 |
| Context window | 1,000,000 | 1,000,000 |
| Lifecycle | active | active |
| License | open-weights | proprietary |
| Trains on API data | Yes | No |
| Zero data retention | on-request | on-request |
| Input per 1M tokens | $0.7 (verified 2026-11-05) | $4 (verified 2026-11-05) |
Frequently asked questions
- Which has the larger context window, Mistral Large 4 or Claude Opus 5.5?
- Mistral Large 4 holds 1,000,000 tokens and Claude Opus 5.5 holds 1,000,000. Both hold 1,000,000 tokens. The context window counts the prompt, any attached files, and the reply together.
- Which is cheaper, Mistral Large 4 or Claude Opus 5.5?
- Per million input tokens, Mistral Large 4 was $0.7 (verified 2026-11-05) and Claude Opus 5.5 was $4 (verified 2026-11-05). Mistral Large 4 is cheaper per input token. Output tokens cost $2.1 and $20 respectively, and output volume usually decides the bill.
- Does Mistral Large 4 or Claude Opus 5.5 train on API data?
- Mistral Large 4 trains on API data by default, and Claude Opus 5.5 does not train on API data by default. Zero data retention is on-request for Mistral Large 4 and on-request for Claude Opus 5.5. Verified 2026-09-08 and 2026-09-08 against the providers' own documentation.
- Is Mistral Large 4 or Claude Opus 5.5 being retired?
- Mistral Large 4 is active. Claude Opus 5.5 is active. Lifecycle checked 2026-11-05 and 2026-11-05. Pin a dated snapshot ID rather than an alias if a retirement would break you.