Choosing a Claude Model
Anthropic offers a family of models at different capability/cost/speed points. Choosing well is mostly about matching the model to the job — and not overpaying for capability you don't need.
The current models
Last verified: 2026-06-20 · Official models & pricing
| Model | API model ID | Tier | Best for |
|---|---|---|---|
| Claude Opus 4.8 | claude-opus-4-8 | Opus — most capable | The hardest reasoning, long-horizon agents, and complex coding where quality matters more than cost. |
| Claude Sonnet 4.6 | claude-sonnet-4-6 | Sonnet — balanced | The default workhorse: strong coding and reasoning at a fraction of Opus cost. Start here for most production work. |
| Claude Haiku 4.5 | claude-haiku-4-5-20251001 | Haiku — fastest & cheapest | High-volume, latency-sensitive tasks: classification, extraction, routing, simple chat, and cheap sub-agents. |
| Fable 5 | claude-fable-5 | Latest generation | One of the newest Claude models. Capabilities and positioning evolve quickly — check the official page above before choosing it. |
Model IDs are exact; tiers and 'best for' are guidance. Pricing, context-window sizes and rate limits change frequently and are intentionally NOT listed here — always read them on the official page above. This file is the single source of truth: never hard-code model facts in prose, link to this table instead.
Try it: which model fits?
Answer three questions and get a starting recommendation:
The balanced default — strong reasoning and coding at a fraction of Opus cost. Start here, and only move up if you hit a real quality ceiling.
Look up the exact model ID on the models table. Rule of thumb only — run a quick eval on your own inputs to be sure.
The mental model: a capability ladder
- Start with Sonnet. It's the default workhorse — strong reasoning and coding at a sensible cost. Most tasks should begin here.
- Move up to Opus only when Sonnet struggles and quality matters more than cost (hard reasoning, tricky agents, gnarly code).
- Drop to Haiku for high-volume, latency-sensitive, or simple work (classification, extraction, routing, cheap sub-agents).
How to actually choose
- Default to Sonnet and ship.
- Hitting a quality ceiling? Try Opus on the hard subset only.
- Cost or latency hurting? See if Haiku is good enough for that step.
- Mix models. Use Haiku for cheap pre/post-processing and Sonnet/Opus for the hard core. This "model tiering" is one of the biggest cost levers — see Cost & Latency.
:::tip Don't pick from benchmarks alone Public benchmarks are a starting hint, not a verdict for your task. Run a tiny eval on a handful of your real inputs across two models — it takes minutes and beats guessing. :::
Looking up the exact model ID
Always pass the current API model ID (e.g. in your messages.create call). Get it from the models table above or the official models page — and prefer reading it from config over hard-coding it in many places, so model upgrades are a one-line change.