Model comparison
Claude Opus 5.5 vs Claude Opus 4.8
- Input
- $4.00
- Output
- $20.00
- Context
- 1M
- Released
- 2026-09-22
- Input
- $5.00
- Output
- $25.00
- Context
- 1M
- Released
- 2026-05-28
Claude Opus 5.5 is cheaper on input tokens ($4 vs $5 per 1M, 1.3×).
Specs and pricing side by side
| Spec | Claude Opus 5.5 | Claude Opus 4.8 |
|---|---|---|
| Maker | Anthropic | Anthropicsame |
| Released | 2026-09-22 | 2026-05-28 |
| Context window | 1M | 1Msame |
| Max output | 128K | 128Ksame |
| Input price | $4.00 | $5.00 |
| Output price | $20.00 | $25.00 |
| Parameters | not published | Undisclosed |
| License | Proprietary | Proprietarysame |
| Weights | API only | API onlysame |
| Modalities | Text, Vision | Text, Visionsame |
| Knowledge cutoff | Jun 2026 | Jan 2026 |
Benchmarks both models report
These two models have no benchmark in common in our registry, so there is no like-for-like score to compare. See each model’s own results: Claude Opus 5.5, Claude Opus 4.8.
Which one should you pick?
Pick Claude Opus 5.5 if…
- Cost matters: input tokens cost 1.3× less ($4 vs $5 per 1M).
- Your use case is: reach for it when an agent has to run for hours across a large codebase and per-token cost, not capability, is the binding constraint.
Pick Claude Opus 4.8 if…
- Your use case is: reach for it when you need the most capable model for multi-step agentic coding across a large codebase.
FAQ
Which is better, Claude Opus 5.5 or Claude Opus 4.8?
Claude Opus 5.5 is cheaper on input tokens ($4 vs $5 per 1M, 1.3×). The better pick depends on whether you value benchmark scores, price per token, context length or openness for your workload.
How much cheaper is Claude Opus 5.5?
Claude Opus 5.5: $4.00 input, $20.00 output. Claude Opus 4.8: $5.00 input, $25.00 output (list API prices as published by each maker).
What are the context windows of Claude Opus 5.5 and Claude Opus 4.8?
Claude Opus 5.5 offers 1M with up to 128K output; Claude Opus 4.8 offers 1M with up to 128K output.
Is Claude Opus 5.5 newer than Claude Opus 4.8?
Claude Opus 5.5 was released 2026-09-22; Claude Opus 4.8 was released 2026-05-28.