Head-to-head showdown: o3-mini ($1.10 in / $4.40 out per 1M) vs Claude Opus 4.8 (OpenRouter) ($5.00 in / $25.00 out per 1M). o3-mini is 5.5× cheaper across standard token mixes, with 200K vs 1M context windows.
o3-mini · openai
claude-opus-4.8 · anthropic
Benchmark
| Workload Scenario | o3-mini | Claude Opus 4.8 (OpenRouter) | Price Delta |
|---|---|---|---|
| 1M input tokens (raw text) | $1.10 | $5.00 | −$3.90 |
| 1M output tokens (generation) | $4.40 | $25.00 | −$20.60 |
| 1M tokens · 70% input / 30% output mix | $2.09 | $11.00 | −$8.91 |
| Standard chat turn (4K in / 800 out, 50% cached) | $0.00682 | $0.031 | −$0.0242 |
| Monthly scale (10K requests / day) | $2,046.00 | $9,300.00 | −$7,254.00 |
Negative difference = o3-mini is cheaper. Positive = Claude Opus 4.8 (OpenRouter) is cheaper.
Scaling Curve
Total cost of a token volume at 70/30 input/output split (uncached). Log-log scale.
Verdict
o3-mini is cheaper on both input and output rates, so it costs less at every input/output mix. Price alone still isn't the whole decision: capability, latency and context limits (o3-mini: 200K, Claude Opus 4.8 (OpenRouter): 1M) may justify the premium for your task.
FAQ
On input, o3-mini is cheaper ($1.10/M vs $5.00/M). On output, o3-mini is cheaper ($4.40/M vs $25.00/M). The same model is cheaper on both sides, so it wins at every mix.
A chat-style request (4,000 input + 800 output tokens, 50% cached) costs $0.00682 on o3-mini and $0.031 on Claude Opus 4.8 (OpenRouter) — o3-mini is 4.5× cheaper for that workload.
o3-mini supports 200,000 tokens (100K max output); Claude Opus 4.8 (OpenRouter) supports 1,000,000 (128K max output). Claude Opus 4.8 (OpenRouter) fits 5.0× more context, which matters for long documents and agents.