Still on Claude Opus 4.1? You pay 3.75× what Opus 5.5 costs
Short answer: Claude Opus 4 and 4.1 cost $15 per million input tokens and $75 per million output tokens. Claude Opus 5.5, the current model of the same tier, costs $4 and $20. For the same traffic, the older model costs 3.75 times more.
| Model | Input, per 1M | Output, per 1M | vs Opus 5.5 |
|---|---|---|---|
| Claude Opus 4 / 4.1 | $15 | $75 | 3.75× |
| Claude Opus 4.5 to 5 | $5 | $25 | 1.25× |
| Claude Opus 5.5 | $4 | $20 | 1× |
What it means in dollars
A team that spends $3,000 a month on Opus 4.1 would pay about $800 for the same tokens on Opus 5.5, a difference of about $2,200 a month or $26,400 a year. The ratio holds for any volume, because both input and output prices dropped by the same factor.
Why teams stay on the old version
- The model name is pinned in code or in a config file nobody revisits.
- A pipeline was tuned years ago and nobody wants to touch it.
- Nobody looks at the bill by model, only at the total.
How to check your own bill
- Open the Claude Console, go to Cost, pick last month and export the file.
- Drop the file on AI Spend Doctor. It runs in your browser and does not upload anything.
- If you still use Opus 4 or 4.1, you will see the exact amount you paid on top.
Check your own bill in 30 seconds
Questions
How much more does Claude Opus 4.1 cost than Opus 5.5?
3.75 times more at list price: $15 versus $4 per million input tokens and $75 versus $20 per million output tokens.
Is Opus 5.5 the same tier as Opus 4.1?
Yes. Both are the Opus tier, Anthropic's top line. Opus 5.5 is the current version. Test quality on your own tasks before switching.
How do I see how much I spend on Opus 4.1?
Export the cost file from the Claude Console and drop it on aispenddoctor.com. It shows spend per model and what you paid on top for older versions.
List prices checked 25 September 2026 on the official Anthropic pricing page. Test quality on your own tasks before switching models. © 2026 Valeriy Danilov. AI Spend Doctor by AgentBridge Labs.