# Claude 3.5 Sonnet API Rate Limits, Pricing & Performance (July 2026)

- Tool: AI API Limits & Performance Matrix
- Last updated: July 2026

## TL;DR

Claude 3.5 Sonnet was dropped from Anthropic's active pricing on February 19, 2026 and is not recommended for new projects. Its successor, Claude Sonnet 5 (claude-sonnet-5), offers 1M token context, introductory pricing at $2.00 input / $10.00 output per MTok (through August 31, 2026), and up to ~50 RPM on the Start tier. Cache reads are excluded from ITPM, effectively multiplying throughput headroom.

## Frequently asked questions

### How do I increase my Claude Sonnet 5 rate limits?

Rate limits increase automatically as your cumulative spend crosses thresholds: ~$40 cumulative moves you from Start to Build, and ~$200 cumulative unlocks the Scale tier (~4,000 RPM / ~2M ITPM per third-party trackers). Above Scale, contact Anthropic sales for a Custom tier with negotiated limits and no spend cap. Monitor your current tier at platform.claude.com/settings/limits or via the Rate Limits API (GET /v1/rate-limits).

### Is the Claude Sonnet 5 API free?

No. There is no free tier for Claude Sonnet 5. The Start tier requires an API key and allows spend up to $500/month, but all token usage is billed. Introductory pricing is $2.00 input / $10.00 output per MTok through August 31, 2026, after which it reverts to $3.00/$15.00.

### Does Claude 3.5 Sonnet still work?

Claude 3.5 Sonnet was dropped from Anthropic's active pricing record on February 19, 2026. The legacy API string remains callable, but Anthropic no longer recommends it for new projects. The current default price/performance model is Claude Sonnet 5 (claude-sonnet-5), released June 30, 2026.

### What does the Claude API rate_limit_error mean?

rate_limit_error (HTTP 429) means you have exceeded one of three limits: RPM (requests per minute), ITPM (input tokens per minute), or OTPM (output tokens per minute). Check the anthropic-ratelimit-requests-remaining and anthropic-ratelimit-tokens-remaining response headers to identify which dimension you hit. The retry-after header tells you how many seconds to wait before retrying.

### How does Claude Sonnet 5 pricing compare to GPT-5?

At introductory rates, Claude Sonnet 5 is $2.00/$10.00 per MTok (input/output) versus GPT-5.5 at approximately $5.00/$30.00. Sonnet 5 also has no long-context surcharge on its 1M context window, while GPT-5.5 charges 2× above 272K tokens. Both offer 50% batch discounts. Note: Sonnet 5 intro pricing ends August 31, 2026.

### Do cache reads count toward Claude Sonnet 5 ITPM limits?

No — cache reads do NOT count toward ITPM for Claude Sonnet 5 (the current non-† model). This is a significant throughput advantage: heavy prompt caching both cuts cost (cache reads = $0.20/MTok vs $2.00 standard input) and preserves ITPM headroom, effectively multiplying your throughput capacity without upgrading tiers.

### Can I use Claude Sonnet 5 on Priority Tier for lower latency?

No. Per Anthropic's service-tiers documentation (July 2026), Claude Sonnet 5 is NOT supported on Priority Tier. This is a per-model restriction, not a tier restriction — even Custom-tier customers cannot access Priority Tier for Sonnet 5. If Priority Tier access is a requirement, Claude Opus 4.8 supports it.

### What's the best way to manage Claude API costs across a team?

Use the Rate Limits API (GET /v1/rate-limits, launched April 25, 2026) to programmatically monitor remaining headroom per dimension. Separate API keys across teams to partition the org-level pool. RapidDev's engineers help teams implement quota management, prompt caching strategies, and model routing to reduce Claude API spend — reach out at rapidevelopers.com/contact for a free scoping call.

### When does Claude Sonnet 5 introductory pricing end?

Introductory pricing ($2.00 input / $10.00 output per MTok) ends August 31, 2026. Starting September 1, 2026, standard pricing takes effect at $3.00 input / $15.00 output per MTok. Batch API pricing also adjusts proportionally. Schedule your high-volume batch workloads before this date to lock in current rates.

---

Source: https://www.rapidevelopers.com/ai-api-limits-performance-matrix/claude-3-5-sonnet
© RapidDev — https://www.rapidevelopers.com/ai-api-limits-performance-matrix/claude-3-5-sonnet