DeepSeek V4 Flash vs GPT-5.4 Pro
DeepSeek V4 Flash and GPT-5.4 Pro are both current production-tier models. DeepSeek V4 Flash is meaningfully cheaper at $0.14 / $0.28 per 1M. DeepSeek V4 Flash has a 1M context window — about 3× the 400k of GPT-5.4 Pro. GPT-5.4 Pro leads on coding, reasoning, general knowledge.
Specs side by side
| Metric | DeepSeek DeepSeek V4 Flash | OpenAI GPT-5.4 Pro |
|---|---|---|
| Input price (per 1M) | $0.14 | $30 |
| Output price (per 1M) | $0.28 | $180 |
| Context window | 1M tokens | 400k tokens |
| Speed tier | balanced | slow |
| Open weights | Yes | No |
| EU region | No | No |
| Free tier | OpenRouter | No |
| Prompt caching | Yes | Yes |
| Vision input | No | Yes |
| Extended thinking | Yes | Yes |
When to choose each
Choose DeepSeek V4 Flash if…
- Cost is a priority ($0.14 / $0.28 per 1M vs $30 / $180 per 1M)
- You need 1M context (3× more than GPT-5.4 Pro)
- You need open weights for self-hosting or fine-tuning
- You want a free tier for prototyping
Choose GPT-5.4 Pro if…
- HIPAA eligibility is required
- You need image input / vision
- Coding is central to your workload
- Reasoning is central to your workload
Benchmark delta
DeepSeek V4 Flash leads on
DeepSeek V4 Flash has no meaningful benchmark lead in this pair.
GPT-5.4 Pro leads on
- Coding
- Reasoning
- General knowledge
- Instruction following
- Multilingual
- Tool use
FAQ — DeepSeek V4 Flash vs GPT-5.4 Pro
DeepSeek V4 Flash vs GPT-5.4 Pro — which is better?
DeepSeek V4 Flash and GPT-5.4 Pro are both current production-tier models. DeepSeek V4 Flash is meaningfully cheaper at $0.14 / $0.28 per 1M. DeepSeek V4 Flash has a 1M context window — about 3× the 400k of GPT-5.4 Pro. GPT-5.4 Pro leads on coding, reasoning, general knowledge. The right pick depends on your use case — see "When to choose each" above for a data-driven decision.
How does DeepSeek V4 Flash pricing compare to GPT-5.4 Pro?
DeepSeek V4 Flash costs $0.14 / $0.28 per 1M vs GPT-5.4 Pro at $30 / $180 per 1M. DeepSeek V4 Flash is cheaper on output tokens by roughly 64186%. Both support prompt caching, which reduces effective cost by 80-90% on repeat system prompts.
Does DeepSeek V4 Flash or GPT-5.4 Pro have the bigger context window?
DeepSeek V4 Flash has a 1M-token context window — 3× the 400k context of GPT-5.4 Pro. Enough for entire codebases, books, or multi-document RAG.
Is there a free tier for DeepSeek V4 Flash or GPT-5.4 Pro?
DeepSeek V4 Flash: yes — Often available free via OpenRouter; official API is extremely cheap ($0.14 cache miss, $0.0028 cached input). GPT-5.4 Pro: no — Paid-only — no free tier.
Which is better for coding — DeepSeek V4 Flash or GPT-5.4 Pro?
GPT-5.4 Pro leads on coding benchmarks (DeepSeek V4 Flash: 89/100, GPT-5.4 Pro: 96/100). For production coding agents also weigh tool-use performance — DeepSeek V4 Flash scores 84, GPT-5.4 Pro scores 94.