Quick answer
Grok documents files api upload size as 50 MB per file. The API exposes separate initialize and chunk-upload operations.
Verified Aug 22, 2026Official source
Current limits
| Constraint | Current value | Scope | Verified source |
|---|---|---|---|
| Files API upload sizeThe API exposes separate initialize and chunk-upload operations. | 50 MB per file | xAI Files API | xAIAug 22, 2026 |
Why does this limit matter?
A Grok app upload allowance should not be assumed to apply to the developer Files API.
This value is scoped to xAI Files API; a different plan, runtime, model, endpoint, region, or account can produce a different effective constraint.
What should you check?
- Measure the encoded upload bytes and use the API-specific endpoint documentation.
- Confirm the exact plan, model, runtime, endpoint, region, and account that serve the failing workload.
- Record the observed value, response headers or configuration, timestamp, and source without logging secrets.
Important caveats
- Public file URLs have a separate 50 MiB publication constraint.
- Treat the official source and live account configuration as authoritative if they differ from this verified snapshot.
HyperObserve reports the documented platform constraint. Your application, SDK, gateway, provider, region, or account can impose a lower effective limit.
Related