Comparison
DeepSeek V4 Flash vs GPT-5.5
GPT-5.5 charges 97% more per input token than DeepSeek V4 Flash. Output pricing favors DeepSeek V4 Flash, 99% less per token than GPT-5.5. GPT-5.5 has the larger context window than DeepSeek V4 Flash.
| Field | DeepSeek V4 Flash | GPT-5.5 |
|---|---|---|
| Provider | DeepSeek | OpenAI |
| Context window | 1M | 1.1M |
| Max output | 384K | 128K |
| Input / 1M | $0.1497% cheaper | $5.00 |
| Output / 1M | $0.2899% cheaper | $30.00 |
| Cached input / 1M | $0.002899% cheaper | $0.50 |
| Batch discount | — | 50% |
| Release date | — | 2026-04-23 |
Worked cost examples
Estimated monthly cost on three common usage shapes
| Workload | DeepSeek V4 Flash | GPT-5.5 |
|---|---|---|
Chatbot 800 input / 200 output tokens per request, 100,000 requests/month | $16.80cheaper | $1,000 |
RAG pipeline 6,000 input / 700 output tokens per request, 30,000 requests/month | $31.08cheaper | $1,530 |
Batch summarization 20,000 input / 1,500 output tokens per request, 5,000 requests/month | $16.10cheaper | $725.00 |
DeepSeek V4 Flash vs GPT-5.5 FAQ
- Is DeepSeek V4 Flash cheaper than GPT-5.5?
- DeepSeek V4 Flash costs $0.14 per 1M input tokens versus $5.00 for GPT-5.5 — DeepSeek V4 Flash is 97% cheaper per input token.
- Which is cheaper for output tokens, DeepSeek V4 Flash or GPT-5.5?
- DeepSeek V4 Flash charges $0.28 per 1M output tokens; GPT-5.5 charges $30.00 per 1M output tokens.
- Which has the larger context window, DeepSeek V4 Flash or GPT-5.5?
- GPT-5.5 does, with a 1,050,000-token context window.
- Do DeepSeek V4 Flash and GPT-5.5 offer cache pricing?
- DeepSeek V4 Flash discounts cached input to $0.0028 per 1M tokens. GPT-5.5 discounts cached input to $0.50 per 1M tokens.
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