DeepSeek V4 Flash vs GPT-5.4 Nano
DeepSeek against OpenAI, costed on the same three workloads. GPT-5.4 Nano is cheaper on all three workloads.
Monthly bill, side by side
| Workload | DeepSeek V4 Flash | GPT-5.4 Nano | Difference |
|---|---|---|---|
| Support chatbot 2,500 six-turn conversations a day |
$1,416 | $907 | $509 (1.6×) |
| Document summariser 1,000 single-shot summaries a day |
$193 | $103 | $89.52 (1.9×) |
| Coding agent 200 twelve-turn sessions a day |
$1,077 | $607 | $471 (1.8×) |
No prompt caching and no batch discount on either side, so the comparison is like for like. Both figures assume 30 days a month.
The rate cards
| DeepSeek V4 Flash | GPT-5.4 Nano | |
|---|---|---|
| Input, per 1M tokens | $0.44 | $0.2 |
| Output, per 1M tokens | $1.32 | $1.25 |
| Cached input | $0.014 | $0.02 |
| Context window | 1M | 272K |
| Maximum output | 384K | 128K |
| Reasoning model | yes | yes |
| Vision | no | yes |
Run this comparison on your own numbers
Full detail: DeepSeek V4 Flash pricing · GPT-5.4 Nano pricing