# Claude Haiku 4.5 vs Claude Sonnet 5.5

Claude Sonnet 5.5 is one of Anthropic's newest models and Claude Haiku 4.5 an earlier one, so this is also what moving up costs or saves. Claude Haiku 4.5 is the cheaper of the 2: for the same tokens, 3 read for each 1 written, Claude Sonnet 5.5 costs 2 times as much. Below are both price lists, what 8 everyday jobs cost a month on each, and how many tokens the same text takes on each, which can change the answer.

- Page, with a calculator for your own job: https://tecyfy.com/prices/compare/claude-haiku-4-5-vs-claude-sonnet-5-5
- Makers: Claude Haiku 4.5 from Anthropic, Claude Sonnet 5.5 from Anthropic

## Price per million tokens, in US dollars

| | Claude Haiku 4.5 | Claude Sonnet 5.5 |
| --- | --: | --: |
| Input | $1 | $2 |
| Cached input | $0.10 | $0.10 |
| Cache write | $1.25 | $2.50 |
| Output | $5 | $10 |
| Blend, 3 read for each 1 written | $2 | $4 |
| Batch input | $0.50 | $1 |
| Batch output | $2.50 | $5 |
| Context window, tokens | 200K | 1M |
| Capability score (Epoch Capabilities Index; GPT-5 is 150) | 142 | 164 |
| Longest answer, tokens | 64K | 128K |

Price change, Claude Sonnet 5.5: Cached input went from $0.20 to $0.10 per million tokens. The price of a cache write did not change.

## What 8 everyday jobs cost a month on each

Each job at its usual runs a day, for 30 days, at the standard price.

| Job | Tokens in, out, runs a day | Claude Haiku 4.5 | Claude Sonnet 5.5 |
| --- | --- | --: | --: |
| A chat question | 300, 500, 100 | $8.40 | $16.80 |
| A hard question, with thinking | 300, 1,400, 100 | $21.90 | $43.80 |
| A long report, summarised | 60,000, 2,000, 20 | $42.00 | $84.00 |
| A 40-turn agent task | 2,800,000, 40,000, 10 | $220 | $364 |
| A support bot's reply | 4,000, 300, 2,000 | $222 | $432 |
| Sort a message into a category | 250, 5, 50,000 | $413 | $825 |
| Read an invoice into fields | 1,500, 250, 1,000 | $82.50 | $165 |
| Review a pull request | 25,000, 4,500, 50 | $71.25 | $143 |

## Questions

### Which is cheaper, Claude Haiku 4.5 or Claude Sonnet 5.5?

Claude Haiku 4.5 is cheaper: $1 per million tokens read and $5 per million written, against $2 and $10 on Claude Sonnet 5.5. On a mix of 3 tokens read for each 1 written, Claude Sonnet 5.5 costs 2 times as much.

### Which is better, Claude Haiku 4.5 or Claude Sonnet 5.5?

On the Epoch Capabilities Index, an independent score from Epoch AI that combines over 50 benchmarks, Claude Sonnet 5.5 scores 164 and Claude Haiku 4.5 142, above the top of the range of doubt around Claude Haiku 4.5's score (GPT-5 is 150). One score is an average; test both on your own work before you switch.

### What does a support bot cost a month on Claude Haiku 4.5 and Claude Sonnet 5.5?

At 2,000 replies a day, each reading 4,000 tokens (50 percent of them from cache) and writing 300, it costs $222 a month on Claude Haiku 4.5 and $432 on Claude Sonnet 5.5: Claude Sonnet 5.5 costs 1.9 times as much for this job.

### What does an AI agent task cost on Claude Haiku 4.5 and Claude Sonnet 5.5?

One 40-turn task that reads 2,800,000 tokens in all, 90 percent of them from cache, and writes 40,000, costs 73 cents on Claude Haiku 4.5 and $1.21 on Claude Sonnet 5.5. At 10 tasks a day that is $220 and $364 a month.

### Which has the larger context window, Claude Haiku 4.5 or Claude Sonnet 5.5?

Claude Sonnet 5.5, with 1M tokens against 200K on Claude Haiku 4.5. The window holds your instructions, the files you attach, the conversation so far and the answer, all at once.

### Does the same text take the same number of tokens on Claude Haiku 4.5 and Claude Sonnet 5.5?

Yes, both are counted the same way: our lesson "How AI writes", 1,700 words long, is about 2,100 to 3,600 tokens on each.

### Is it cheaper to move from Claude Haiku 4.5 to Claude Sonnet 5.5?

No, it costs more per token: Claude Sonnet 5.5 charges $2 per million tokens read and $10 written, against $1 and $5 on Claude Haiku 4.5, 2 times as much for the same tokens. It pays off only if better answers save more than that, for example in fewer retries.

### Can I pay less on Claude Haiku 4.5 and Claude Sonnet 5.5 for work that can wait?

Yes, on both. With a batch, where you collect the answers later instead of at once, Claude Haiku 4.5 costs $0.50 per million tokens read and $2.50 written, and Claude Sonnet 5.5 $1 and $5.

## Sources

- [Anthropic: API prices](https://platform.claude.com/docs/en/about-claude/pricing)
- [Epoch Capabilities Index, by Epoch AI (CC BY 4.0)](https://epoch.ai/benchmarks/eci)

## Other comparisons

- [Claude Mythos 5.1 vs Claude Sonnet 5.5](https://tecyfy.com/prices/compare/claude-mythos-5-1-vs-claude-sonnet-5-5.md)
- [Claude Fable 5 vs Claude Sonnet 5.5](https://tecyfy.com/prices/compare/claude-fable-5-vs-claude-sonnet-5-5.md)
- [Claude Mythos 5 vs Claude Sonnet 5.5](https://tecyfy.com/prices/compare/claude-mythos-5-vs-claude-sonnet-5-5.md)
- [Claude Opus 5 vs Claude Sonnet 5.5](https://tecyfy.com/prices/compare/claude-opus-5-vs-claude-sonnet-5-5.md)
- [Claude Opus 4.8 vs Claude Sonnet 5.5](https://tecyfy.com/prices/compare/claude-opus-4-8-vs-claude-sonnet-5-5.md)
- [Claude Opus 4.7 vs Claude Sonnet 5.5](https://tecyfy.com/prices/compare/claude-opus-4-7-vs-claude-sonnet-5-5.md)