DeepSeek V4 Flash vs GPT-5.4

DeepSeek V4 Flash and GPT-5.4 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. GPT-5.4 leads on coding, reasoning, general knowledge.

Specs side by side

Metric
DeepSeek
DeepSeek V4 Flash
OpenAI
GPT-5.4
Input price (per 1M)$0.14$2.5
Output price (per 1M)$0.28$15
Context window1M tokens400k tokens
Speed tierbalancedbalanced
Open weightsYesNo
EU regionNoYes
Free tierOpenRouterNo
Prompt cachingYesYes
Vision inputNoYes
Extended thinkingYesYes

When to choose each

DeepSeek Free tier

Choose DeepSeek V4 Flash if…

  • Cost is a priority ($0.14 / $0.28 per 1M vs $2.5 / $15 per 1M)
  • You need 1M context (3× more than GPT-5.4)
  • You need open weights for self-hosting or fine-tuning
  • You want a free tier for prototyping
OpenAI

Choose GPT-5.4 if…

  • EU data residency is required
  • 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 leads on

  • Coding
  • Reasoning
  • General knowledge
  • Instruction following
  • Multilingual
  • Tool use

FAQ — DeepSeek V4 Flash vs GPT-5.4

DeepSeek V4 Flash vs GPT-5.4 — which is better?

DeepSeek V4 Flash and GPT-5.4 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. GPT-5.4 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?

DeepSeek V4 Flash costs $0.14 / $0.28 per 1M vs GPT-5.4 at $2.5 / $15 per 1M. DeepSeek V4 Flash is cheaper on output tokens by roughly 5257%. Both support prompt caching, which reduces effective cost by 80-90% on repeat system prompts.

Does DeepSeek V4 Flash or GPT-5.4 have the bigger context window?

DeepSeek V4 Flash has a 1M-token context window — 3× the 400k context of GPT-5.4. Enough for entire codebases, books, or multi-document RAG.

Is there a free tier for DeepSeek V4 Flash or GPT-5.4?

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: no — Free $5 credit for new accounts; paid thereafter.

Which is better for coding — DeepSeek V4 Flash or GPT-5.4?

GPT-5.4 leads on coding benchmarks (DeepSeek V4 Flash: 89/100, GPT-5.4: 93/100). For production coding agents also weigh tool-use performance — DeepSeek V4 Flash scores 84, GPT-5.4 scores 93.