Claude Sonnet 5.5 vs Claude Opus 5.5
A plain comparison: what they do, what they cost and which to pick for your task.
In short
Sonnet 5.5 costs half as much and covers most tasks. Switch to Opus 5.5 when Sonnet falls short: hard code, big analysis, an important text.
Claude Sonnet 5.5 is cheaper: an answer costs 2 times less than with Claude Opus 5.5.
Side by side
| Claude Sonnet 5.5 | Claude Opus 5.5 | |
|---|---|---|
| Maker | Anthropic, USA | Anthropic, USA |
| Type | everyday | flagship |
| Good for | Claude’s everyday model. Natural writing and good code, the best value of the line. | Claude’s flagship for hard writing, code and analysis. Half the price of Fable and handles most difficult tasks. |
| Official, $ per 1M | $2 / $10 | $4 / $20 |
| Freepay rate | ×1 / ×5 | ×2 / ×10 |
| Maker’s subscription | Claude Pro costs about $20 a month. | Claude Pro costs about $20 a month. |
Prices: your text / answer. The “Freepay rate” shows how many balance tokens a model spends per token of its own; Claude Sonnet 5.5 is ×1.
Which to pick for the task
| Task | Better |
|---|---|
| Everyday tasks | Claude Sonnet 5.5 |
| Hard code | Claude Opus 5.5 |
| Deep analysis | Claude Opus 5.5 |
| Price | Claude Sonnet 5.5 |
The best way to choose is to ask both models the same question. On Freepay you do it in one chat, switching the model in the input field.
About Claude Sonnet 5.5
Claude’s everyday model. Natural writing and good code, the best value of the line. Claude is made by Anthropic, a US company. People pick it for natural writing, strong code and the way it handles long documents. More about Claude Sonnet 5.5.
About Claude Opus 5.5
Claude’s flagship for hard writing, code and analysis. Half the price of Fable and handles most difficult tasks. More about Claude Opus 5.5.
Frequently asked questions
Which is better, Claude Sonnet 5.5 or Claude Opus 5.5?
Sonnet 5.5 costs half as much and covers most tasks. Switch to Opus 5.5 when Sonnet falls short: hard code, big analysis, an important text.
Which is cheaper, Claude Sonnet 5.5 or Claude Opus 5.5?
Claude Sonnet 5.5 is cheaper: an answer costs 2 times less than with Claude Opus 5.5. Official prices per 1M tokens: Claude Sonnet 5.5 $2 / $10, Claude Opus 5.5 $4 / $20. On Freepay both are 10x cheaper.
Can I use Claude Sonnet 5.5 and Claude Opus 5.5 in one place?
Yes. On Freepay both models are in one chat, you switch them in the input field, and the balance is shared.
Do I need two subscriptions for Claude Sonnet 5.5 and Claude Opus 5.5?
No. On claude.ai you need an account and a phone number, the free plan has tight message limits, and Claude Pro is a monthly subscription. On Freepay one key covers both, with no subscription.