How much does Claude Sonnet 4.5 cost?

Claude Sonnet 4.5 costs $3 per million input tokens, the text it reads, and $15 per million output tokens, the text it writes, thinking included. On a mix of 3 tokens read for each 1 written, that is $6 per million.

How much does cached input cost on Claude Sonnet 4.5?

Text Claude Sonnet 4.5 reads again from the cache costs $0.30 per million tokens, against $3 the first time. Putting text in the cache costs $3.75 per million, so a long prompt sent again and again costs far less after the first time.

Does Claude Sonnet 4.5 have a batch price?

Yes. With a batch, where you send many requests and collect the answers later instead of at once, Claude Sonnet 4.5 costs $1.50 per million tokens read and $7.50 per million written.

What is the context window of Claude Sonnet 4.5?

Claude Sonnet 4.5 holds 200K tokens at once, about 300 pages of English text, and writes up to 64K tokens in one answer. The window holds your instructions, the files you attach, the conversation so far and the answer.

How good is Claude Sonnet 4.5?

Claude Sonnet 4.5 scores 147 on the Epoch Capabilities Index, an independent score from Epoch AI that combines over 50 benchmarks, with a range of doubt from 145 to 148 (GPT-5 is 150). One score is an average; test it on 10 tasks of your own.

Is there a cheaper model as good as Claude Sonnet 4.5?

Claude Haiku 5.5 from Anthropic scores 159 on the Epoch Capabilities Index, about as well or better, and costs $0.20 per million on a mix of 3 tokens read for each 1 written: Claude Sonnet 4.5 costs 30 times as much. Test both on your own work before you switch.

Should I still use Claude Sonnet 4.5?

It is still sold, so it keeps working, but Anthropic's newest models are Claude Fable 5.1, Claude Opus 5.5, Claude Sonnet 5.5 and Claude Haiku 5.5. Compare its price with theirs below, and run your own tasks on the newer model before you move.

What does a support bot cost a month on Claude Sonnet 4.5?

At 2,000 replies a day, each reading 4,000 tokens (50 percent of them from cache) and writing 300, a support bot costs 1.1 cents a reply on Claude Sonnet 4.5, $666 a month.

What does an AI agent task cost on Claude Sonnet 4.5?

One 40-turn task that reads 2,800,000 tokens in all, 90 percent of them from cache, and writes 40,000, costs $2.20 on Claude Sonnet 4.5. At 10 tasks a day that is $659 a month.

Claude Sonnet 4.5 API pricing

Claude Sonnet 4.5 is an earlier Anthropic model, still sold. It costs $3 per million tokens it reads and $15 per million it writes, $6 on a mix of 3 read for each 1 written. Anthropic's newest models are Claude Fable 5.1, Claude Opus 5.5, Claude Sonnet 5.5 and Claude Haiku 5.5. Below are every price Anthropic lists for it, and what 8 everyday jobs cost a month on it.

Price your own job Compare it

Input: $3 per million tokens read
Output: $15 per million tokens written
On everyday work: $6 per million, 3 read for each 1 written
Context window: 200K tokens at once
Capability score: 147 on the Epoch Capabilities Index, GPT-5 is 150

Every Claude Sonnet 4.5 price, per million tokens

In US dollars, as Anthropic prints them on its price page.

InputTokens the model reads	$3
Cached inputRead again from the cache	$0.30
Cache writePutting text in the cache	$3.75
OutputTokens it writes, thinking included	$15
Blend 3:13 tokens read for each 1 written	$6
Batch inputAnswers collected later	$1.50
Batch output	$7.50
Context windowTokens it holds at once	200K tokens
Longest answerTokens it writes in 1 reply	64K tokens

Every model’s prices, free to use: JSON or CSV.

What 8 everyday jobs cost a month on Claude Sonnet 4.5

Each job at its usual number of runs a day, for 30 days, at the standard price. Open any job in the cost calculator to change its size, or to set it beside every other model.

Job	A run	A month
A chat question300 in, 500 out, 100 a day	0.84 cents	$25.20
A hard question, with thinking300 in, 1,400 out, 100 a day	2.2 cents	$65.70
A long report, summarised60,000 in, 2,000 out, 20 a day	21 cents	$126
A 40-turn agent task2,800,000 in, 40,000 out, 10 a day	$2.20	$659
A support bot's reply4,000 in, 300 out, 2,000 a day	1.1 cents	$666
Sort a message into a category250 in, 5 out, 50,000 a day	0.083 cents	$1,238
Read an invoice into fields1,500 in, 250 out, 1,000 a day	0.83 cents	$248
Review a pull request25,000 in, 4,500 out, 50 a day	14 cents	$214

Cheaper models that score as well as Claude Sonnet 4.5

Newest models with a lower blend price whose Epoch Capabilities Index score is about as high or higher, cheapest first. A score is an average over many benchmarks, so test one on your own work before you switch.

Claude Haiku 5.5Anthropic
$0.20
per million at 3:1, score 159
Side by side
GPT-6 LunaOpenAI
$0.20
per million at 3:1, score 156
Side by side
DeepSeek V4.1 FlashDeepSeek
$0.525
per million at 3:1, score 156
Side by side
Gemini 3.8 FlashGoogle
$1.50
per million at 3:1, score 157
Side by side

Compare Claude Sonnet 4.5

Both price lists side by side, and what the same 8 jobs cost on each.

Compare any 2 models

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How to read a model's prices

Every maker prints 2 main prices: one for the tokens a model reads (input) and one for the tokens it writes (output), each per million tokens. Writing costs more on almost every model, so a job that reads a long document and writes a line pays mostly the input price, and a chat that writes paragraphs pays mostly the output price. The blend, 3 tokens read for each 1 written, is one figure for ranking models on everyday work.

The other prices lower or raise the bill. Text read again from a cache costs a fraction of the input price, so a long system prompt or document sent with every request gets cheaper after the first. Work that can wait a day costs about half on a batch where the maker offers one. Some models charge more for every token once a prompt passes a set length.

Thinking is billed as output, and the same text is not the same number of tokens on every model, so the price per token is only the start. Each job below is priced the way the cost calculator prices it, at its usual runs a day for 30 days; open one to change its size, or compare the model with another side by side.

Questions

How much does Claude Sonnet 4.5 cost?: Claude Sonnet 4.5 costs $3 per million input tokens, the text it reads, and $15 per million output tokens, the text it writes, thinking included. On a mix of 3 tokens read for each 1 written, that is $6 per million.
How much does cached input cost on Claude Sonnet 4.5?: Text Claude Sonnet 4.5 reads again from the cache costs $0.30 per million tokens, against $3 the first time. Putting text in the cache costs $3.75 per million, so a long prompt sent again and again costs far less after the first time.
Does Claude Sonnet 4.5 have a batch price?: Yes. With a batch, where you send many requests and collect the answers later instead of at once, Claude Sonnet 4.5 costs $1.50 per million tokens read and $7.50 per million written.
What is the context window of Claude Sonnet 4.5?: Claude Sonnet 4.5 holds 200K tokens at once, about 300 pages of English text, and writes up to 64K tokens in one answer. The window holds your instructions, the files you attach, the conversation so far and the answer.
How good is Claude Sonnet 4.5?: Claude Sonnet 4.5 scores 147 on the Epoch Capabilities Index, an independent score from Epoch AI that combines over 50 benchmarks, with a range of doubt from 145 to 148 (GPT-5 is 150). One score is an average; test it on 10 tasks of your own.
Is there a cheaper model as good as Claude Sonnet 4.5?: Claude Haiku 5.5 from Anthropic scores 159 on the Epoch Capabilities Index, about as well or better, and costs $0.20 per million on a mix of 3 tokens read for each 1 written: Claude Sonnet 4.5 costs 30 times as much. Test both on your own work before you switch.
Should I still use Claude Sonnet 4.5?: It is still sold, so it keeps working, but Anthropic's newest models are Claude Fable 5.1, Claude Opus 5.5, Claude Sonnet 5.5 and Claude Haiku 5.5. Compare its price with theirs below, and run your own tasks on the newer model before you move.
What does a support bot cost a month on Claude Sonnet 4.5?: At 2,000 replies a day, each reading 4,000 tokens (50 percent of them from cache) and writing 300, a support bot costs 1.1 cents a reply on Claude Sonnet 4.5, $666 a month.
What does an AI agent task cost on Claude Sonnet 4.5?: One 40-turn task that reads 2,800,000 tokens in all, 90 percent of them from cache, and writes 40,000, costs $2.20 on Claude Sonnet 4.5. At 10 tasks a day that is $659 a month.

Sources