DeepSeek: R1 0528 vs OpenAI: GPT-5.1-Codex-Mini
Head-to-head API pricing and cost comparison between DeepSeek’s DeepSeek: R1 0528 and OpenAI’s OpenAI: GPT-5.1-Codex-Mini. Prices auto-refresh daily from OpenRouter.
OpenAI: GPT-5.1-Codex-Mini is 50% cheaper for input tokens; OpenAI: GPT-5.1-Codex-Mini also wins on output tokens.
Side-by-side comparison
| Spec | DeepSeek: R1 0528 | OpenAI: GPT-5.1-Codex-Mini |
|---|---|---|
| Input price (per 1M) | $0.50 | $0.25 |
| Cached input (per 1M) | $0.35 | $0.02 |
| Output price (per 1M) | $2.15 | $2.00 |
| Batch input (per 1M) | — | $0.13 |
| Batch output (per 1M) | — | $1.00 |
| Reasoning price (per 1M) | — | — |
| Context window | 164K | 400K |
| Vision support | No | Yes |
| Caching support | Yes | Yes |
| Batch API | No | Yes |
| Reasoning capability | No | No |
Monthly cost at volume
Estimated monthly API spend at common production traffic levels (input/output tokens per request shown).
| Volume | DeepSeek: R1 0528 | OpenAI: GPT-5.1-Codex-Mini | Savings |
|---|---|---|---|
1K req/day 500in / 200out tokens | $20.40 | $15.75 | $4.65 OpenAI: GPT-5.1-Codex-Mini wins |
10K req/day 1500in / 500out tokens | $547.50 | $412.50 | $135.00 OpenAI: GPT-5.1-Codex-Mini wins |
100K req/day 3000in / 800out tokens | $9,660 | $7,050 | $2,610 OpenAI: GPT-5.1-Codex-Mini wins |
1M req/day 8000in / 2000out tokens | $249,000 | $180,000 | $69,000 OpenAI: GPT-5.1-Codex-Mini wins |
Adjust input/output token counts, request volume, batch & cached pricing.
Related comparisons
Frequently asked questions
Which is cheaper, DeepSeek: R1 0528 or OpenAI: GPT-5.1-Codex-Mini?
For input tokens, OpenAI: GPT-5.1-Codex-Mini is roughly 50% cheaper at $0.25/1M vs $0.50/1M. For output tokens, OpenAI: GPT-5.1-Codex-Mini wins at $2.00/1M. Real-world cost depends on your input/output ratio — use the calculator to model your actual workload.
What’s the context window difference?
DeepSeek: R1 0528 has a context window of 164K tokens. OpenAI: GPT-5.1-Codex-Mini offers 400K tokens. Larger context windows are valuable for long documents, RAG pipelines, and multi-turn conversations — but they come with higher input-token bills if you fill them every request.
Should I use DeepSeek: R1 0528 or OpenAI: GPT-5.1-Codex-Mini?
Choose DeepSeek: R1 0528 if you’re already on the DeepSeek stack, want broad ecosystem support, or prefer its feature set. Choose OpenAI: GPT-5.1-Codex-Mini for OpenAI’s ecosystem, native vision input, or its cheaper input tokens. Run a small benchmark on your own prompts before committing — price is only one axis.
How are these prices kept current?
Prices are pulled directly from OpenRouter’s public models API once every 24 hours via a Convex cron job, then normalized to per-1M-token figures. Last refresh: May 28, 2026.