I use Claude Haiku 4.5 for small refactors, code review, and debugging. Those jobs benefit more from quick responses and lower cost than from the deeper reasoning I would pay Sonnet for.
The Numbers
| Model | Input (1M tokens) | Output (1M tokens) |
|---|---|---|
| Haiku 4.5 | $0.80 | $4 |
| Sonnet 4.5 | $3 | $15 |
At these published token prices, Haiku is 3.75 times cheaper. That gap matters when a workflow makes many calls.
Where I Use It
For these bounded tasks, the faster response makes the tool feel more immediate. Sonnet earns its price when I need complex reasoning or nuanced writing.
January 2025 Cutoff
The cutoff matters All three recent Claude models (Haiku, Sonnet 4.5, Opus 4.1) have a January 2025 knowledge cutoff. Provide context in your prompt when working with newer frameworks or libraries.
Established patterns and refactoring work fine, but bleeding-edge tools require extra context in your prompts.
When Cost Decides
Haiku makes LLM integration practical for projects where API costs would otherwise kill the idea. You can afford to be generous with calls. It will not impress on reasoning, but it does not need to.
Related posts:
- Claude Code’s Strengths and Weaknesses in March 2025 - See how Haiku compares to other Claude tools
- GPT-4.1: SWE-bench Performance - Compare Haiku to GPT-4.1 on coding benchmarks
- The True Cost of AI - Understand AI pricing across different models and services
One quick signal
Did this earn your time?
Thanks. That gives me something concrete to check.
About the author
KahWee Teng
I’m a staff software engineer focused on frontend systems and developer experience. I write from migrations, measured tradeoffs, and tools tested in real work.
