Model Comparison

DeepSeek-R1 vs GPT-5 CodexWhich is better in 2026?

Comparing DeepSeek-R1 and GPT-5 Codex across benchmarks, pricing, and capabilities.

Verdict: DeepSeek-R1 vs GPT-5 Codex — which is better?

DeepSeek-R1 (by DeepSeek) and GPT-5 Codex (by OpenAI) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.

Choose DeepSeek-R1 if…

  • you need open weights you can self-host or fine-tune

Choose GPT-5 Codex if…

  • you want the most recent training data — it shipped Sep 2025

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

DeepSeek-R1 and GPT-5 Codexdon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Arena Performance

Human preference votes

Context Window

Maximum input and output token capacity

Only DeepSeek-R1 specifies input context (131,072 tokens). Only DeepSeek-R1 specifies output context (131,072 tokens).

DeepSeek
DeepSeek-R1
Input131,072 tokens
Output131,072 tokens
OpenAI
GPT-5 Codex
Input- tokens
Output- tokens
Sat Jun 27 2026 • llm-stats.com

License

Usage and distribution terms

DeepSeek-R1 is licensed under MIT, while GPT-5 Codex uses a proprietary license.

License differences may affect how you can use these models in commercial or open-source projects.

DeepSeek-R1

MIT

Open weights

GPT-5 Codex

Proprietary

Closed source

Release Timeline

When each model was launched

DeepSeek-R1 was released on 2025-01-20, while GPT-5 Codex was released on 2025-09-15.

GPT-5 Codex is 8 months newer than DeepSeek-R1.

DeepSeek-R1

Jan 20, 2025

1.4 years ago

GPT-5 Codex

Sep 15, 2025

9 months ago

7mo newer

Knowledge Cutoff

When training data ends

GPT-5 Codex has a documented knowledge cutoff of 2024-09-30, while DeepSeek-R1's cutoff date is not specified.

We can confirm GPT-5 Codex's training data extends to 2024-09-30, but cannot make a direct comparison without DeepSeek-R1's cutoff date.

DeepSeek-R1

—

GPT-5 Codex

Sep 2024

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

DeepSeek
Larger context window (131,072 tokens)
Has open weights
OpenAI

No standout differentiators in the data we have for this pair.

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against DeepSeek-R1 and GPT-5 Codex side-by-side, then vote on the output you prefer.

DeepSeek-R1
✓ Preferred
GPT-5 Codex
Open in Playground
AI Model Comparison Table
Feature
DeepSeek
DeepSeek-R1
OpenAI
GPT-5 Codex

FAQ

Common questions about DeepSeek-R1 vs GPT-5 Codex.

Which is better, DeepSeek-R1 or GPT-5 Codex?

DeepSeek-R1 (DeepSeek) and GPT-5 Codex (OpenAI) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.

How does DeepSeek-R1 compare to GPT-5 Codex in benchmarks?

GPT-5 Codex scores SWE-Bench Verified: 74.5%.

What are the context window sizes for DeepSeek-R1 and GPT-5 Codex?

DeepSeek-R1 supports 131K tokens and GPT-5 Codex supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between DeepSeek-R1 and GPT-5 Codex?

Key differences include licensing (MIT vs Proprietary). See the full comparison above for benchmark-by-benchmark results.

Who makes DeepSeek-R1 and GPT-5 Codex?

DeepSeek-R1 is developed by DeepSeek and GPT-5 Codex is developed by OpenAI.

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