Claude API Cost Calculator
What does the Claude API really cost per month? This TokenForge preset answers it for Anthropic's lineup — Fable 5, Opus 4.8, Sonnet 5 and Haiku 4.5 — including the one thing most price tables miss: Claude's newest models tokenize the same text into roughly 30% more tokens, and this calculator corrects for it. Prices refresh daily.
Claude API cost tool
At 50M tokens/month, the API is cheaper by $1,875.70/month.
† Anthropic's newest models (Fable 5, Opus 4.8, Sonnet 5) tokenize the same text into ~30% more tokens; the calculator corrects for this. Prices exclude batch (−50%) and prompt-caching discounts.
What Claude costs per month (July 2026)
| Claude model | Input $/1M | Output $/1M | Blended @4:1* | 50M/mo | 500M/mo |
|---|---|---|---|---|---|
| Claude Fable 5 | $10.00 | $50.00 | $23.40 | $1,170 | $11,700 |
| Claude Opus 4.8 | $5.00 | $25.00 | $11.70 | $585 | $5,850 |
| Claude Sonnet 5 | $2.00 | $10.00 | $4.68 | $234 | $2,340 |
| Claude Haiku 4.5 | $1.00 | $5.00 | $1.80 | $90 | $900 |
*Blended prices for Fable 5, Opus 4.8 and Sonnet 5 include the ~30% tokenizer correction — they are what a million GPT-style tokens effectively costs, so the rows are directly comparable with other providers. Haiku 4.5 uses a conventional tokenizer and needs no correction.
How the bill is calculated
blended $/1M = (ratio × input price + output price) ÷ (ratio + 1) × tokenizer factormonthly bill = tokens per month (M) × blended $/1M
Worked example. A document-analysis pipeline processing 2,500 reports a day at roughly 2,400 input and 600 output tokens each uses about 225M tokens/month at 4:1. On Claude Sonnet 5 that text expands to ≈292M Claude tokens, and the bill lands at 225 × $4.68 = $1,053/month. The same volume on Haiku 4.5 — no tokenizer penalty — costs 225 × $1.80 = $405.
Choosing a Claude model — and what the token factor means
Four tiers, one decision: how much quality does the task need? Claude Fable 5 is the frontier flagship at $10 in / $50 out per 1M — reserved for the hardest reasoning and agentic work. Opus 4.8 sits just below it, Sonnet 5 is the mainstream default that most products build on, and Haiku 4.5 handles high-volume, latency-sensitive work at a fifth of Sonnet's blended price. Route by task difficulty and the bill drops fast without hurting the output where it matters.
The tokenizer factor is real money, so this page refuses to hide it. Anthropic's list prices look competitive per million tokens, but the newest Claude models split identical text into roughly 30% more tokens than OpenAI-style tokenizers — Sonnet 5's "$2.00 input" behaves like $2.60 per GPT-equivalent million. TokenForge bakes the factor into every blended price above (marked †), so when you compare Claude against GPT or Gemini in the dropdown, the comparison is honest.
Prompt caching is Claude's biggest discount — use it. Cache reads cost about 90% less than fresh input ($0.20 vs $2.00 per 1M on Sonnet 5), and agent workloads that resend long system prompts, tool definitions or document context on every call are exactly the shape caching rewards. Batch processing halves prices again for asynchronous jobs. The calculator shows undiscounted list prices, so a well-engineered workload should land meaningfully below its number.
Know where the API stops making sense. Against a rented H100 at the preset assumptions, self-hosting an open-weights model overtakes Sonnet 5 from about 451M tokens/month — and Fable 5 from as little as ~90M. If your volume is anywhere near those lines, start by estimating your real monthly token usage, then run the numbers in the main calculator or the self-hosting comparison.
Frequently asked questions
Related tools and guides
- LLM Token Cost Calculator — the main tool, with all providers and servers
- OpenAI API Cost Calculator — the same bill for GPT-5.6 and GPT-5.4 tiers
- Gemini API Cost Calculator — Google's tiers from budget Flash-Lite to Gemini 3.1 Pro
- How to estimate your monthly LLM token usage — get the volume number this bill depends on