o3 Paid vs 
Claude Opus 5.5 Paid
o3 vs Claude Opus 5.5 compared — price per token, context window, multimodality, openness and which to choose. Full 2026 breakdown.
o3 — full profile › · Claude Opus 5.5 — full profile ›
Prices & specs refreshed from live data · olud.ai
Open-model prices = cheapest provider via OpenRouter; official maker rates may be higher.
$8 /M outputManaged API (no infra to run)
$20 /M outputManaged API (no infra to run)
o3 vs Claude Opus 5.5 specs
| Spec | o3 | Claude Opus 5.5 | Winner |
|---|---|---|---|
| Maker | OpenAI | Anthropic | – |
| Type | Proprietary | Proprietary | – |
| Context window | 200K tokens | 1M tokens | |
| Input price | $2/M | $4/M | |
| Output price | $8/M | $20/M | |
| Vision / multimodal | Yes | Yes | = Tie |
| Tool / function calling | Yes | Yes | = Tie |
| Self-hostable | No (API only) | No (API only) | – |
| License | Proprietary | Proprietary | – |
Price gap & when to choose each
o3 is ~2.5× cheaper than Claude Opus 5.5 on output tokens ($8 vs $20 per M tokens).
- You want frontier performance through a managed API
- You want the lower output price
- You value reliability & ecosystem
- You don't want to manage infrastructure
- You want frontier performance through a managed API
- You need the longer 1M context window
- You value reliability & ecosystem
- You don't want to manage infrastructure
Feature comparison
| Capability | o3 | Claude Opus 5.5 |
|---|---|---|
| Open weights (downloadable) | ✗ | ✗ |
| Self-hostable | ✗ | ✗ |
| Runs fully offline | ✗ | ✗ |
| Vision / multimodal | ✓ | ✓ |
| Tool / function calling | ✓ | ✓ |
| 1M+ context window | ✗ | ✓ |
Benchmarks: o3 vs Claude Opus 5.5
Independent benchmark scores measured by Artificial Analysis. Higher is better (except latency).
Benchmark data by Artificial Analysis.
How o3 and Claude Opus 5.5 score
| Criterion | o3 | Claude Opus 5.5 |
|---|---|---|
| Cost-efficiency | 3.5 | 3.0 |
| Context window | 4.0 | 5.0 |
| Openness | 1.5 | 1.5 |
| Self-hosting | 1.0 | 1.0 |
| Multimodality | 5.0 | 5.0 |
Scores come from live data — output price (cost), context length, open vs closed weights (openness & self-hosting) and vision/tool support (multimodality). Raw task quality isn't scored here; it depends on your benchmark — see the verdict.
What each model is
o3 Paid
o3 is a well-rounded and powerful model across domains. It sets a new standard for math, science, coding, and visual reasoning tasks. It also excels at technical writing and instruction-following....
Claude Opus 5.5 Paid
Claude Opus 5.5 is Anthropic's flagship model for demanding reasoning, coding, and long-horizon agentic work, succeeding Claude Opus 5. It is particularly strong at multi-step changes in large codebases, code...
Other models in these families
These variants are tracked but not compared here — one page per family keeps the comparison readable.
Frequently asked questions
o3 vs Claude Opus 5.5 — which is cheaper?
o3 is cheaper on output ($8/M vs $20/M).
Which has the larger context window?
Claude Opus 5.5 offers the larger context window (1M tokens).
o3 vs Claude Opus 5.5 — which should I pick in 2026?
Choose o3 for the lower output price ($8/M vs $20/M). Choose Claude Opus 5.5 if you need the larger 1M context window.
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