DeepSeek V4 Flash vs GPT-5.5 Pro
At a Glance
| Compare |  DeepSeek V4 FlashDeepSeek |  GPT-5.5 ProOpenAI |
|---|---|---|
| Pricing and Limits | ||
| Input priceFrom · USD / 1M tokens | $0.0868Openrouter ↗ · Aug 28, 2026 | $30.00Openai ↗ · Sep 3, 2026 |
| Output priceFrom · USD / 1M tokens | $0.1736Openrouter ↗ · Aug 28, 2026 | $180.00Openai ↗ · Sep 3, 2026 |
| Context windowMaximum documented tokens | 1,049K | 1,050K |
| Model facts checked | Aug 28, 2026View model evidence → | Sep 3, 2026View model evidence → |
Token prices are the lowest available sourced USD rates; input and output may use different providers. Cost ranking estimates output spend on LiveBench, not a full request bill. Ranking methodology →
Available Benchmarks
| Benchmark | DeepSeek-V4-Flash | GPT-5.5 Pro |
|---|---|---|
| ARC-AGI-1verified-v1-ba05d69f6453 · verified_score · leader | 89.0092% of row best · percent · DeepSeek V4 Flash 0731 (Max) | 96.50100% of row best · percent · GPT-5.5 Pro (High) |
| ARC-AGI-2verified-v2-6c676fa3e9af · verified_score · leader | 61.3973% of row best · percent · DeepSeek V4 Flash 0731 (Max) | 84.58100% of row best · percent · GPT-5.5 Pro (High) |
| Overall ResultCounted from the protocol-matched rows above | 0 benchmark winsNo overall winner | 2 benchmark winsNo overall winner |
Third-party benchmark Only like-for-like primary-publisher results are shown; raw scores, relative scores, configuration, and token spend remain visible.
Side-by-Side Facts
| Field | DeepSeek-V4-Flash | GPT-5.5 Pro |
|---|---|---|
| Developer | DeepSeek | OpenAI |
| Family | Deepseek V4 Flash | Gpt 5 5 |
| Model | DeepSeek-V4-Flash | GPT-5.5 Pro |
| Version | DeepSeek-V4-Flash | GPT-5.5 Pro |
| Lifecycle | retired | active |
| Released | 2026-04-24 | 2026-04-23 |
| Knowledge cutoff | Unknown | 2025-12-01 |
| Input modalities | Text | Text, Image |
| Output modalities | Text | Text |
| Context window | 1,049K | 1,050K |
| Total parameters | 290.9B | Unknown |
| Active parameters | 13B | Unknown |
| License | mit | Unknown |
| Open weights | Yes | No |
| API available | Yes | Yes |
| Self-hostable | Yes | No |
| Provider access | DeepSeek (Standard), Deepinfra (Standard), Fireworks Ai (Standard), Hugging Face (Standard), Openrouter (Standard) | Openai (Standard), Openrouter (Standard) |
| Capabilities | chat, generation, reasoning | chat, generation, reasoning, structured_outputs, tools |
DeepSeek V4 Flash Capabilities
GPT-5.5 Pro Capabilities
Related Comparisons
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|---|---|---|---|
DeepSeek-V4-FlashDeepSeek | vs | GPT-6 AstraOpenAI | cross-developer peerstext |
Claude Fable 5.1Anthropic | vs | DeepSeek-V4-FlashDeepSeek | cross-developer peerstext |
DeepSeek-V4-FlashDeepSeek | vs |  Gemini 3.1 ProGoogle DeepMind | cross-developer peerstext |
DeepSeek-V4-FlashDeepSeek | vs | DeepSeek-V4.1-FlashDeepSeek | family variantstext |
DeepSeek-V4-FlashDeepSeek | vs | Grok 4.6xAI | cross-developer peerstext |
DeepSeek-V4-FlashDeepSeek | vs |  Qwen3.8-MaxQwen | cross-developer peerstext |
DeepSeek-V4-FlashDeepSeek | vs |  Kimi-K3Moonshot AI | cross-developer peerstext |
 MiniMax-M3MiniMax | vs | DeepSeek-V4-FlashDeepSeek | cross-developer peerstext |
DeepSeek-V4-FlashDeepSeek | vs |  GLM-5.3Z.ai | cross-developer peerstext |
DeepSeek-V4-FlashDeepSeek | vs |  Hy4 previewTencent | cross-developer peerstext |
Seed 2.1 ProByteDance Seed | vs | DeepSeek-V4-FlashDeepSeek | cross-developer peerstext |
DeepSeek-V4-FlashDeepSeek | vs |  Mistral Large 3Mistral AI | cross-developer peerstext |
Primary Evidence
Sources and Freshness
Questions
DeepSeek V4 Flash vs GPT-5.5 Pro FAQs
Is DeepSeek V4 Flash or GPT-5.5 Pro better for coding?+
This comparison does not currently contain a protocol-matched coding benchmark for both DeepSeek V4 Flash and GPT-5.5 Pro, so Model Markets cannot name a coding leader from pricing, context size, or capability labels alone.
Which is cheaper, DeepSeek V4 Flash or GPT-5.5 Pro?+
DeepSeek V4 Flash is $0.0868 and GPT-5.5 Pro is $30.00 per million tokens, so DeepSeek V4 Flash is cheaper on this metric. DeepSeek V4 Flash is $0.1736 and GPT-5.5 Pro is $180.00 per million tokens, so DeepSeek V4 Flash is cheaper on this metric.
Which has a larger context window, DeepSeek V4 Flash or GPT-5.5 Pro?+
GPT-5.5 Pro has the larger sourced context window. DeepSeek V4 Flash supports 1,049K and GPT-5.5 Pro supports 1,050K.
Which performs better in benchmarks, DeepSeek V4 Flash or GPT-5.5 Pro?+
There is no overall benchmark winner: An overall winner requires at least two decisive benchmarks from at least two original publishers.
Can DeepSeek V4 Flash or GPT-5.5 Pro be self-hosted?+
DeepSeek V4 Flash is the only model in this pair currently marked as self-hostable. DeepSeek V4 Flash is open weight; GPT-5.5 Pro is not marked open weight.
Can DeepSeek V4 Flash and GPT-5.5 Pro understand images?+
DeepSeek V4 Flash is not documented with image input; GPT-5.5 Pro is documented with image input. This reflects supported input modalities, not vision quality.
Which can generate longer answers, DeepSeek V4 Flash or GPT-5.5 Pro?+
Neither has a larger sourced maximum output. DeepSeek V4 Flash is — and GPT-5.5 Pro is 128K.
Do DeepSeek V4 Flash and GPT-5.5 Pro support reasoning and tool use?+
DeepSeek V4 Flash: reasoning. GPT-5.5 Pro: reasoning, tool calling, and image input. Feature support does not establish relative quality.
Which is available from more inference providers, DeepSeek V4 Flash or GPT-5.5 Pro?+
DeepSeek V4 Flash has 5 sourced provider routes; GPT-5.5 Pro has 2, so DeepSeek V4 Flash has broader tracked availability.
Which offers better value, DeepSeek V4 Flash or GPT-5.5 Pro?+
There is no universal value winner. Compare the input and output prices above with the matched benchmark result for your workload: cheaper tokens can be offset by different quality, token usage, latency, or provider availability.