PUBLISHED PROVIDER LIMITS
Limits keep their provider-specific dimensions.
Limits vary by usage tier and model class. Short bursts can be constrained more tightly than a simple per-minute average.
Authentication: Anthropic API key
Primary scope: Organization With Optional Workspace Limits
Measured dimensions: Requests Per Minute, Input Tokens Per Minute, Output Tokens Per Minute
Profile coverage: Standard Messages API request and token dimensions, usage-tier spend caps, standard rate-limit headers, and 429 behavior. Message Batches, Managed Agents, Priority Tier, fast mode, and account-specific numeric rate tables are outside this profile.
Rate limits
| Limit | Value | Period | Scope | Conditions and variability |
|---|---|---|---|---|
| Messages API rate limits | Provider-specific | Provider-defined | Organization And Model Class | Varies by usage tier, model class, workspace configuration, and account-specific limits. Read configured values from the Claude Console or Rate Limits API. |
Spend limits
| Limit | Value | Period | Scope | Conditions and variability |
|---|---|---|---|---|
| Start tier monthly spend cap | 500 USD | Per calendar month | Organization | Published provider limit. |
| Build tier monthly spend cap | 1,000 USD | Per calendar month | Organization | Published provider limit. |
| Scale tier monthly spend cap | 200,000 USD | Per calendar month | Organization | Published provider limit. |
RESPONSE METADATA
Headers expose the applicable limit state.
Retry-AfterFormat: Seconds- Seconds to wait before retrying.
Anthropic-RateLimit-Requests-LimitFormat: Integer- Maximum requests allowed within the active request rate-limit period.
Anthropic-RateLimit-Requests-RemainingFormat: Integer- Requests remaining before being rate limited.
Anthropic-RateLimit-Requests-ResetFormat: Rfc3339- Time when request capacity will be fully replenished.
Anthropic-RateLimit-Tokens-LimitFormat: Integer- Maximum combined token allowance within the active period when applicable.
Anthropic-RateLimit-Tokens-RemainingFormat: Integer- Tokens remaining, rounded to the nearest thousand.
Anthropic-RateLimit-Tokens-ResetFormat: Rfc3339- Time when token capacity will be fully replenished.
Anthropic-RateLimit-Input-Tokens-LimitFormat: Integer- Maximum input tokens allowed within the active period.
Anthropic-RateLimit-Input-Tokens-RemainingFormat: Integer- Input tokens remaining, rounded to the nearest thousand.
Anthropic-RateLimit-Input-Tokens-ResetFormat: Rfc3339- Time when input-token capacity will be fully replenished.
Anthropic-RateLimit-Output-Tokens-LimitFormat: Integer- Maximum output tokens allowed within the active period.
Anthropic-RateLimit-Output-Tokens-RemainingFormat: Integer- Output tokens remaining, rounded to the nearest thousand.
Anthropic-RateLimit-Output-Tokens-ResetFormat: Rfc3339- Time when output-token capacity will be fully replenished.
WHEN A LIMIT IS EXCEEDED
Read the response before choosing a delay.
- Rate-limit responses can use HTTP 429.
- 429 responses can also result from acceleration limits when traffic increases sharply.
RECOMMENDED HANDLING
Protect both the provider and your own queue.
- Honor Retry-After.
- Ramp traffic gradually.
- Use prompt caching where appropriate because cached input tokens do not count toward ITPM for most models.
- Read account-specific limits from the Console or Rate Limits API.
VERIFICATION RECORD