Claude Opus 4.8 vs Claude Sonnet 4
A side-by-side comparison of two multimodal models — real specs, pricing, strengths and weaknesses, and a clear verdict on which to choose. Kept current by our agents.
Quick verdict: which should you choose?
Choose Claude Opus 4.8 if you need
- ✓Need the only reported intelligence index of 55.7 and nuanced reasoning over million-token inputs
- ✓Require explicit multimodal handling of text, images, and files together
- ✓Value robust safety alignment with careful, detailed outputs
- ✓Can accept $25/1M pricing and potential higher latency on large contexts
Choose Claude Sonnet 4 if you need
- ✓Want the lower $15/1M output price for comparable 1M context length
- ✓Prioritize strong reasoning and coherence without needing the 55.7 intelligence score
- ✓Prefer high-quality detailed responses with effective multimodal integration at reduced cost
- ✓Operate under budget constraints where unknown speed and intelligence metrics are acceptable
Verdict
Claude Opus 4.8 leads on measured intelligence (55.7) and documented multimodal strength with text/images/files, while Claude Sonnet 4 undercuts it on price at $15 vs $25 per million tokens. Both share identical 1M context windows and Anthropic safety tuning, but Opus provides the only quantified speed (65.39 t/s). Sonnet 4 remains attractive where cost matters more than the extra intelligence index points.
Claude Opus 4.8 vs Claude Sonnet 4: side by side
| Spec | Claude Opus 4.8 | Claude Sonnet 4 | Winner |
|---|---|---|---|
| Intelligence | 55.7 | — | Tie |
| Output speed | 65 t/s | — | Tie |
| Output price | $25.00/1M | $15.00/1M | Claude Sonnet 4 |
| Context | 1000K | 1000K | Tie |
| Params | — | — | Tie |
| Provider | Anthropic | Anthropic | Tie |
Detailed analysis
Pricing
Winner: Claude Sonnet 4Claude Sonnet 4 lists $15 per million tokens versus Claude Opus 4.8 at $25 per million tokens. Both are proprietary Anthropic models with identical 1M context. The $10 difference favors Sonnet 4 for high-volume use.
Intelligence & Reasoning
Winner: Claude Opus 4.8Only Claude Opus 4.8 reports an intelligence_index of 55.7. Its strengths explicitly include careful and nuanced reasoning plus strong multimodal integration of text, images, and files. Sonnet 4 lists strong reasoning but supplies no index value.
Speed & Context
Winner: TieBoth models share a 1,000,000-token context window. Claude Opus 4.8 alone provides output_speed of 65.39 t/s; Sonnet 4 leaves speed unreported. Latency notes appear only for Opus on large contexts.
Multimodal & Safety
Winner: TieOpus highlights strong integration of text, images, and files with robust safety alignment. Sonnet 4 notes effective multimodal integration and careful safety alignment but lists no native audio or video support. Both exhibit conservative tendencies from safety tuning.
Claude Opus 4.8
Pros
- +Handles extremely long inputs effectively
- +Strong multimodal integration of text, images, and files
- +Careful and nuanced reasoning
Cons
- –Higher latency on large contexts
- –Conservative response style due to safety tuning
- –May require explicit guidance for creative tasks
Claude Sonnet 4
Pros
- +Strong reasoning and coherence over long inputs
- +Careful safety alignment
- +High-quality, detailed responses
Cons
- –Conservative refusals on sensitive topics
- –No native audio or video support
- –May prioritize caution over maximum helpfulness
Summary: Claude Opus 4.8 vs Claude Sonnet 4
Choose Claude Opus 4.8 when the 55.7 intelligence index, explicit image-and-file multimodal support, and nuanced reasoning justify the higher $25 price. Select Claude Sonnet 4 when the $15 rate and comparable 1M context suffice without needing the published intelligence metric.
Frequently asked questions
Claude Opus 4.8 shows stronger documented multimodal integration of text, images, and files plus the only intelligence index (55.7); Sonnet 4 offers effective integration at lower cost but lacks the quantified score.