Model Comparison

DeepSeek-V4-Flash-0731 vs o1-previewWhich is better in 2026?

Comparing DeepSeek-V4-Flash-0731 and o1-preview across benchmarks, pricing, and capabilities.

Verdict: DeepSeek-V4-Flash-0731 vs o1-preview — which is better?

DeepSeek-V4-Flash-0731 (by DeepSeek) and o1-preview (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.

On price, DeepSeek-V4-Flash-0731 is roughly 233.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

DeepSeek-V4-Flash-0731 also accepts a larger context window (1,048,576 input tokens), making it the stronger choice for long documents and large codebases.

Choose DeepSeek-V4-Flash-0731 if…

  • cost matters — it's about 233.3x cheaper per token
  • you process long inputs — it offers a 1,048,576 token context window
  • you want the most recent training data — it shipped Jul 2026
  • you need open weights you can self-host or fine-tune

Choose o1-preview if…

  • you want predictable pricing at $15.00/M input and $60.00/M output

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

DeepSeek-V4-Flash-0731 and o1-previewdon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

DeepSeek-V4-Flash-0731 costs less

For input processing, DeepSeek-V4-Flash-0731 ($0.09/1M tokens) is 166.7x cheaper than o1-preview ($15.00/1M tokens).

For output processing, DeepSeek-V4-Flash-0731 ($0.18/1M tokens) is 333.3x cheaper than o1-preview ($60.00/1M tokens).

In conclusion, o1-preview is more expensive than DeepSeek-V4-Flash-0731.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Mon Aug 03 2026 • llm-stats.com
DeepSeek
DeepSeek-V4-Flash-0731
Input tokens$0.09
Output tokens$0.18
Best providerDeepinfra
OpenAI
o1-preview
Input tokens$15.00
Output tokens$60.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

DeepSeek-V4-Flash-0731 accepts 1,048,576 input tokens compared to o1-preview's 128,000 tokens. DeepSeek-V4-Flash-0731 can generate longer responses up to 65,536 tokens, while o1-preview is limited to 32,768 tokens.

DeepSeek
DeepSeek-V4-Flash-0731
Input1,048,576 tokens
Output65,536 tokens
OpenAI
o1-preview
Input128,000 tokens
Output32,768 tokens
Mon Aug 03 2026 • llm-stats.com

License

Usage and distribution terms

DeepSeek-V4-Flash-0731 is licensed under MIT, while o1-preview uses a proprietary license.

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

DeepSeek-V4-Flash-0731

MIT

Open weights

o1-preview

Proprietary

Closed source

Release Timeline

When each model was launched

DeepSeek-V4-Flash-0731 was released on 2026-07-31, while o1-preview was released on 2024-09-12.

DeepSeek-V4-Flash-0731 is 23 months newer than o1-preview.

DeepSeek-V4-Flash-0731

Jul 31, 2026

3 days ago

1.9yr newer
o1-preview

Sep 12, 2024

1.9 years ago

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Provider Availability

DeepSeek-V4-Flash-0731 is available from DeepInfra, Fireworks, Novita. o1-preview is available from OpenAI, Azure.

DeepSeek-V4-Flash-0731

deepinfra logo
Deepinfra
Input Price:Input: $0.09/1MOutput Price:Output: $0.18/1M
fireworks logo
Fireworks
Input Price:Input: $0.14/1MOutput Price:Output: $0.28/1M
novita logo
Novita
Input Price:Input: $0.14/1MOutput Price:Output: $0.28/1M

o1-preview

openai logo
OpenAI
Input Price:Input: $15.00/1MOutput Price:Output: $60.00/1M
azure logo
Azure
Input Price:Input: $16.50/1MOutput Price:Output: $66.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

DeepSeek
Larger context window (1,048,576 tokens)
Less expensive input tokens
Less expensive output 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-V4-Flash-0731 and o1-preview side-by-side, then vote on the output you prefer.

DeepSeek-V4-Flash-0731
✓ Preferred
o1-preview
Open in Playground
AI Model Comparison Table
Feature
DeepSeek
DeepSeek-V4-Flash-0731
OpenAI
o1-preview

FAQ

Common questions about DeepSeek-V4-Flash-0731 vs o1-preview.

Which is better, DeepSeek-V4-Flash-0731 or o1-preview?

DeepSeek-V4-Flash-0731 (DeepSeek) and o1-preview (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-V4-Flash-0731 compare to o1-preview in benchmarks?

DeepSeek-V4-Flash-0731 scores Terminal-Bench 2.1: 82.7%, CyberGym: 76.7%, Toolathlon: 70.3%, DSBench-FullStack: 68.7%, DSBench-Hard: 59.6%. o1-preview scores MGSM: 90.8%, MMLU: 90.8%, MATH: 85.5%, GPQA: 73.3%, LiveBench: 52.3%.

Is DeepSeek-V4-Flash-0731 cheaper than o1-preview?

DeepSeek-V4-Flash-0731 is 166.7x cheaper for input tokens. DeepSeek-V4-Flash-0731 costs $0.09/M input and $0.18/M output via deepinfra. o1-preview costs $15.00/M input and $60.00/M output via openai.

What are the context window sizes for DeepSeek-V4-Flash-0731 and o1-preview?

DeepSeek-V4-Flash-0731 supports 1.0M tokens and o1-preview supports 128K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between DeepSeek-V4-Flash-0731 and o1-preview?

Key differences include context window (1.0M vs 128K), input pricing ($0.09 vs $15.00/M), licensing (MIT vs Proprietary). See the full comparison above for benchmark-by-benchmark results.

Who makes DeepSeek-V4-Flash-0731 and o1-preview?

DeepSeek-V4-Flash-0731 is developed by DeepSeek and o1-preview is developed by OpenAI.

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