Claude Opus 4.5 vs DeepSeek-V4-Flash-0731
Comparing Claude Opus 4.5 and DeepSeek-V4-Flash-0731 across benchmarks, pricing, and capabilities.
Anthropic · DeepSeek · Updated for 2026
Which is better?
Claude Opus 4.5 and DeepSeek-V4-Flash-0731 trade strengths across price, capabilities, and technical limits. The better choice depends on the workload.
On price, DeepSeek-V4-Flash-0731 is roughly 88.9x 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.
Based on current benchmark, pricing, and model metadata for 2026.
Choose Claude Opus 4.5
- you want predictable pricing at $5.00/M input and $25.00/M output
Choose DeepSeek-V4-Flash-0731
- cost matters — it's about 88.9x 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
At a glance
The differences that matter most.
Performance Benchmarks
Comparative analysis across standard metrics
Claude Opus 4.5 and DeepSeek-V4-Flash-0731don't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.
Arena Performance
Playground indexes and blind preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Claude Opus 4.5 ($5.00/1M tokens) is 55.6x more expensive than DeepSeek-V4-Flash-0731 ($0.09/1M tokens).
For output processing, Claude Opus 4.5 ($25.00/1M tokens) is 138.9x more expensive than DeepSeek-V4-Flash-0731 ($0.18/1M tokens).
In conclusion, Claude Opus 4.5 is more expensive than DeepSeek-V4-Flash-0731.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
DeepSeek-V4-Flash-0731 accepts 1,048,576 input tokens compared to Claude Opus 4.5's 200,000 tokens. DeepSeek-V4-Flash-0731 can generate longer responses up to 65,536 tokens, while Claude Opus 4.5 is limited to 64,000 tokens.
Input Capabilities
Supported data types and modalities
Claude Opus 4.5 supports multimodal inputs, whereas DeepSeek-V4-Flash-0731 does not.
Claude Opus 4.5 can handle both text and other forms of data like images, making it suitable for multimodal applications.
Claude Opus 4.5
DeepSeek-V4-Flash-0731
License
Usage and distribution terms
Claude Opus 4.5 is licensed under a proprietary license, while DeepSeek-V4-Flash-0731 uses MIT.
License differences may affect how you can use these models in commercial or open-source projects.
Proprietary
Closed source
MIT
Open weights
Release Timeline
When each model was launched
Claude Opus 4.5 was released on 2025-11-24, while DeepSeek-V4-Flash-0731 was released on 2026-07-31.
DeepSeek-V4-Flash-0731 is 8 months newer than Claude Opus 4.5.
Nov 24, 2025
9 months ago
Jul 31, 2026
3 weeks ago
8mo newerKnowledge Cutoff
When training data ends
Claude Opus 4.5 has a documented knowledge cutoff of 2025-03-31, while DeepSeek-V4-Flash-0731's cutoff date is not specified.
We can confirm Claude Opus 4.5's training data extends to 2025-03-31, but cannot make a direct comparison without DeepSeek-V4-Flash-0731's cutoff date.
Mar 2025
—
Provider Availability
Claude Opus 4.5 is available from Anthropic. DeepSeek-V4-Flash-0731 is available from DeepInfra, Novita, Fireworks.
Claude Opus 4.5
DeepSeek-V4-Flash-0731
Outputs Comparison
Judge for yourself.
Run your own prompts against Claude Opus 4.5 and DeepSeek-V4-Flash-0731 side-by-side, then vote on the output you prefer.
FAQ
Common questions about Claude Opus 4.5 vs DeepSeek-V4-Flash-0731.