API cost decision in 10 seconds

R1 0528 vs GPT-5.1-Codex-Mini

Pick GPT-5.1-Codex-Mini when budget and context both matter.

Page updated: 2026-05-26T15:08:08Z Data confirmed: 2026-05-26T19:08:13Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick GPT-5.1-Codex-Mini when budget and context both matter.

On the standard 1M input plus 500K output workload, GPT-5.1-Codex-Mini is estimated at $1.25 vs $1.57 for R1 0528, saving $0.32 (20.6% lower).

Cost-first pickGPT-5.1-Codex-Mini

Context-first pickGPT-5.1-Codex-Mini

Sample savings$0.3220.6%

10x traffic gap$3.25

GPT-5.1-Codex-Mini is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $3.25. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

GPT-5.1-Codex-Mini stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shape	Token mix	Better pick	R1 0528	GPT-5.1-Codex-Mini
Input-heavy / RAG	5M input + 500K output	GPT-5.1-Codex-Mini	$3.58	$2.25
Balanced workload	1M input + 1M output	GPT-5.1-Codex-Mini	$2.65	$2.25
Output-heavy chatbot	1M input + 5M output	GPT-5.1-Codex-Mini	$11.25	$10.25

Cheaper input GPT-5.1-Codex-Mini $0.5 vs $0.25 / 1M

GPT-5.1-Codex-Mini is $0.25 cheaper per 1M input tokens (50% lower; 2x difference).

Cheaper output GPT-5.1-Codex-Mini $2.15 vs $2 / 1M

GPT-5.1-Codex-Mini is $0.15 cheaper per 1M output tokens (7% lower; 1.07x difference).

Larger context GPT-5.1-Codex-Mini 163.84K vs 400K

GPT-5.1-Codex-Mini has 236.16K more context (2.44x larger).

Sample workload GPT-5.1-Codex-Mini $1.57 vs $1.25

GPT-5.1-Codex-Mini is $0.32 cheaper on the standard workload (20.6% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.

Monthly input tokens Monthly output tokens

R1 0528 Calculating… Estimated API cost

GPT-5.1-Codex-Mini Calculating… Estimated API cost

Cheaper for this workload Calculating… Difference: calculating…

This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.

Quick Decision

Verdict

GPT-5.1-Codex-Mini has the lower input price; GPT-5.1-Codex-Mini has the lower output price; GPT-5.1-Codex-Mini offers the larger context window. For the 1M input plus 500K output sample, GPT-5.1-Codex-Mini is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $1.57 for R1 0528 and $1.25 for GPT-5.1-Codex-Mini.

Best Fit

Choose R1 0528 when its provider, model quality, latency, or availability is more important than the numeric price/context winner.

Choose GPT-5.1-Codex-Mini when you care most about lower input-token price, lower output-token price, and larger context window.

Decision Notes

On the standard 1M input plus 500K output workload, GPT-5.1-Codex-Mini is estimated at $1.25 vs $1.57 for R1 0528, saving $0.32 (20.6% lower).
GPT-5.1-Codex-Mini is $0.32 cheaper on the standard workload (20.6% lower).
GPT-5.1-Codex-Mini is $0.25 cheaper per 1M input tokens (50% lower; 2x difference).
GPT-5.1-Codex-Mini is $0.15 cheaper per 1M output tokens (7% lower; 1.07x difference).
GPT-5.1-Codex-Mini has 236.16K more context (2.44x larger).

Head-to-Head Specs

Feature	R1 0528 (DeepSeek)	GPT-5.1-Codex-Mini (OpenAI)
Input Price prompt tokens per 1M	$0.5	$0.25
Completion Price per 1M tokens	$2.15	$2
Sample Workload Cost 1M input + 500K output	$1.57	$1.25
Context Window	163.84K	400K
Release Date	2025-05-28	2025-11-13
Popularity	#106	#141

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	GPT-5.1-Codex-Mini	On the standard 1M input plus 500K output workload, GPT-5.1-Codex-Mini is estimated at $1.25 vs $1.57 for R1 0528, saving $0.32 (20.6% lower).
High-volume input processing	GPT-5.1-Codex-Mini	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	GPT-5.1-Codex-Mini	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	GPT-5.1-Codex-Mini	A larger context window leaves more room for retrieved passages, conversation history, or source files.

Related Alternatives

Same-provider lower-cost swaps

DeepSeek V4 Flash (free) can replace R1 0528 when lower sample workload cost matters most: $0.
DeepSeek V4 Flash can replace R1 0528 when lower sample workload cost matters most: $0.2.
R1 Distill Qwen 32B can replace R1 0528 when lower sample workload cost matters most: $0.43.
DeepSeek V3.2 can replace R1 0528 when lower sample workload cost matters most: $0.44.

Larger context near this budget

Llama 4 Scout offers 10M context with $0.23 sample workload cost.
Owl Alpha offers 1.05M context with $0 sample workload cost.
DeepSeek V4 Flash offers 1.05M context with $0.2 sample workload cost.
DeepSeek V4 Pro offers 1.05M context with $0.87 sample workload cost.

Popular competitors

DeepSeek V4 Flash · DeepSeek · #1
Hy3 preview · Tencent · #2
Claude Opus 4.7 · Anthropic · #3
Claude Sonnet 4.6 · Anthropic · #4

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Provider catalogs

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DeepSeek catalog

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OpenAI catalog

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R1 0528

May 28th update to the [original DeepSeek R1](/deepseek/deepseek-r1) Performance on par with [OpenAI o1](/openai/o1), but open-sourced and with fully open reasoning tokens. It's 671B parameters in size, with 37B active...

GPT-5.1-Codex-Mini

GPT-5.1-Codex-Mini is a smaller and faster version of GPT-5.1-Codex