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LLM Cost per Million Words Calculator

What it costs to have Claude, GPT or Gemini read or write a million words, with words converted to tokens for you.

Updated · By Niraj Kumar · 6 sources

Model

Each request

Count text inCount text in
words

About 1,333 tokens. System prompt, conversation history, documents and tool definitions are all resent on every call.

words

About 1,333 tokens. The visible answer.

Count tokens from a prompt or JSON payloadShow

Plain text, OpenAI Chat or Responses JSON, or Anthropic Messages JSON. A final assistant message or a response body counts as output. Counted in your browser; nothing is uploaded.

Loading the tokenizer…

Counts use OpenAI's o200k tokenizer, so they are exact for GPT-6 and GPT-5 models, plus a few tokens of message framing. Other providers' tokenizers count the same text differently and do not publish a conversion factor; Anthropic says Claude models from 4.7 on produce about 30% more tokens than earlier Claude models. For an exact count on another model, paste one of its API responses: the usage it reports is shown above.

tokens

Thinking tokens are billed as output. Leave at 0 for models or settings that do not reason.

Volume

PricePrice

Discounts

%
0%100%

The share of input that repeats exactly at the start of every request, such as a fixed system prompt. The prompt caching calculator prices cache writes and expiry in detail.

Batch APIBatch API
Total for the job$16.00$0.016 a request on Claude Sonnet 5
Per 1,000 requests
$16.00
Input
$2.67
Output
$13.33
Price rank
15th cheapest of 24
Cheapest listed model
Claude Haiku 5.5
$0.80 for the job, $15.20 less
Output83%
  • Input17%
  • Output83%
Every model on this workload, for the whole job1,333 tokens in, 1,333 out, 1,000 requests. Hover or focus a row for rates.
  1. 1Claude Haiku 5.5Anthropic$0.80
  2. 2GPT-6 LunaOpenAI$0.80
  3. 3Qwen3.8 FlashAlibaba$0.826
  4. 4GPT-5.6 LunaOpenAI$1.87
  5. 5DeepSeek V4.1 FlashDeepSeek$2.00
  6. 6Qwen3.7 PlusAlibaba$2.67
  7. 7Gemini 3.5 Flash-LiteGoogle$3.73
  8. 8Grok 4.3xAI$5.00
  9. 9Gemini 3.8 FlashGoogle$6.00
  10. 10DeepSeek V4 ProDeepSeek$7.04
  11. 11Claude Haiku 4.5Anthropic$8.00
  12. 12Grok 4.7xAI$10.66
  13. 13Qwen3.8 MaxAlibaba$10.66
  14. 14Claude Sonnet 5.5Anthropic$16.00
  15. 15Claude Sonnet 5Anthropic$16.00
  16. 16GPT-6.1 SolOpenAI$16.00
  17. 17GPT-6 SolOpenAI$16.00
  18. 18GPT-5.6 TerraOpenAI$18.66
  19. 19Gemini 3.1 ProGoogle$18.66
  20. 20Claude Opus 5.5Anthropic$31.99
  21. 21GPT-5.6 SolOpenAI$31.99
  22. 22Claude Opus 5Anthropic$39.99
  23. 23Claude Fable 5.1Anthropic$79.98
  24. 24GPT-6 AstraOpenAI$79.98

How the LLM Cost per Million Words Calculator works

cost = (fresh input × input rate + cached input × cache rate + (output + reasoning) × output rate) ÷ 1,000,000

This page uses the same method as the LLM API Cost Calculator, which explains each term and assumption in full.

Worked example

1,000 requests of 1,000 words in and 1,000 words out: a million words read and a million written, as a one-off job. At about 1.33 tokens a word, that is roughly 1.33 million tokens each way. Priced on Claude Sonnet 5.

  1. 1Each request: 1,333 input tokens, 1,333 output
  2. 2Input costs $0.00267 and output $0.0133, so $0.016 a request
  3. 3× 1,000 requests = $16.00

$16.00 for the job on Claude Sonnet 5. The cheapest listed model, Claude Haiku 5.5, would cost $0.80.

Frequently asked questions

How many tokens is a million words?

About 1.33 million tokens of ordinary English prose, at roughly three-quarters of a word per token. Technical writing, code, names and non-English text take more tokens per word, sometimes much more, and each provider's tokenizer counts slightly differently.

Why does writing a million words cost more than reading them?

Every provider prices output tokens four to eight times higher than input, because generating each token takes a full pass through the model. Reading a million words is therefore a small part of the bill next to writing a million. Toggle the output down to zero in the calculator to see the reading cost alone.

Sources

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