Your organization is placed on a usage tier automatically and moves up over time. Each tier caps monthly spend and per-model requests/tokens per minute. Here's every number, sourced from Anthropic's docs, not estimated.
| Tier | Monthly spend cap |
|---|---|
| Start | $500 |
| Build | $1,000 |
| Scale | $200,000 |
| Custom | No cap (negotiated) |
Hit your spend cap and API usage pauses until next month unless you request a higher limit. You can also self-set a lower spend limit below your tier's cap in Console → Settings → Limits.
Limits are set per model class using the token bucket algorithm (continuously replenished, not reset on a fixed clock). Opus 4.5–4.8 share one combined limit; Sonnet 4.5/4.6 share another, separate from Sonnet 5.
| Model | Start RPM | Start ITPM | Start OTPM |
|---|---|---|---|
| Claude Sonnet 5 | 1,000 | 2,000,000 | 400,000 |
| Claude Opus 4.x* | 1,000 | 2,000,000 | 400,000 |
| Claude Haiku 4.5 | 1,000 | 2,000,000 | 400,000 |
| Claude Fable 5 | 1,000 | 500,000 | 100,000 |
| Model | Build RPM | Build ITPM | Build OTPM |
|---|---|---|---|
| Claude Sonnet 5 | 5,000 | 5,000,000 | 1,000,000 |
| Claude Opus 4.x* | 5,000 | 5,000,000 | 1,000,000 |
| Claude Haiku 4.5 | 5,000 | 5,000,000 | 1,000,000 |
| Claude Fable 5 | 2,000 | 1,500,000 | 300,000 |
| Model | Scale RPM | Scale ITPM | Scale OTPM |
|---|---|---|---|
| Claude Sonnet 5 | 10,000 | 10,000,000 | 2,000,000 |
| Claude Opus 4.x* | 10,000 | 10,000,000 | 2,000,000 |
| Claude Haiku 4.5 | 10,000 | 10,000,000 | 2,000,000 |
| Claude Fable 5 | 4,000 | 4,000,000 | 800,000 |
*Opus limit is one combined bucket across Opus 4.8, 4.7, 4.6, and 4.5. Need more than Scale? That's the Custom tier — contact sales, no self-serve path.
The detail that actually changes how you should build: for most models, only input_tokens (post-cache-breakpoint) and cache_creation_input_tokens count toward ITPM — cache_read_input_tokens does not. With a 2,000,000 ITPM limit and an 80% cache hit rate, you can effectively push through 10,000,000 total input tokens/minute (2M uncached + 8M served from cache). Claude Haiku 3.5 is the one exception (marked † in Anthropic's tables) — it counts cache reads toward ITPM like everyone else's naive TPM limit does.
OTPM is metered on tokens actually generated, not on max_tokens — setting a high max_tokens costs nothing extra against this limit if the model stops early.
| Surface | Limit behavior |
|---|---|
| Message Batches API | Separate pool: 1,000–4,000 RPM by tier, plus a 100k–500k queued-batch-request cap — doesn't draw from your Messages API RPM/ITPM/OTPM. |
| Managed Agents (create) | 300 requests/min, org-wide, separate from Messages API limits. |
| Managed Agents (read/list/stream) | 1,200 requests/min. |
inference_geo: "us" vs "global" | Same rate-limit pool — data residency changes price (1.1x), not your limit. |
| Fast mode (Opus 4.7/4.8, research preview) | Its own dedicated limit, separate from standard Opus RPM/TPM. |
Every response carries anthropic-ratelimit-requests-remaining, -input-tokens-remaining, and -output-tokens-remaining headers plus matching -reset timestamps (RFC 3339) — poll those instead of guessing. A 429 also returns retry-after in seconds; retrying before that elapses will just fail again. Watch too for acceleration limits: a sharp usage spike can trip a 429 even under your steady-state cap, so ramp traffic up gradually rather than switching a new workload on at full volume.
Use the full calculator to price the token side once you know your throughput, or see tool use pricing for what web search/code execution add on top of plain tokens, and Batch API pricing if your workload can tolerate async processing instead of live RPM limits entirely.