Claude Haiku vs Sonnet: cost, quality, and when to use which
The price gap between Claude tiers is large, so the single biggest lever on a Claude bill is often just running each task on the smallest model that still does the job.
What Haiku handles well
Classification, extraction, routing, short summaries, and structured transforms — high-volume, low-ambiguity work. On these, Haiku's quality is usually indistinguishable from Sonnet at a fraction of the cost.
When you actually need Sonnet (or Opus)
Multi-step reasoning, nuanced writing, and hard tool use benefit from the bigger models. The trick is not to default everything to the top tier — route only the hard slice up, guarded by an eval.
Turn this into your number
Drop your usage export into the free analyzer and see how much of this applies to your account — provable savings separated from estimates. Nothing is uploaded.
Analyze my usage — freeFAQ
- How much does downgrading actually save?
- It depends on how much of your traffic is easy. The free analyzer shows your top-tier share and the ceiling you'd recover by routing the easy portion down — as an estimate, since only an eval can confirm quality holds.