Claude Haiku 5.5 vs DeepSeek V4.1 Flash: pricing compared

For a 30-step coding agent run, DeepSeek V4.1 Flash is 1.4x cheaper ($0.09 vs $0.12). Prices verified 2026-10-18.

Claude Haiku 5.5DeepSeek V4.1 Flash
ProviderAnthropicDeepSeek
Input / 1M$0.10$0.30
Cached input / 1M$0.01$0.006
Output / 1M$0.50$1.20
Batch discount50%—
Context window1M1M
Long-context tierabove 100Knone

Cost on real workloads

WorkloadClaude Haiku 5.5DeepSeek V4.1 Flash
10,000 chatbot replies
2,000 input + 400 output tokens each, 50% of the prompt cached
$3.10$7.86
One 30-step coding agent run
12K system + tools prompt, 1K output and 3K tool result per step, caching on
$0.12$0.09
1M documents classified (batch)
600 input + 20 output tokens each, batch API where available
$35.00$204

Price is only half the decision: a cheaper model that needs more steps or retries can cost more per finished task. Run your own numbers in the calculator (both models pinned), or see how both rank in the use-case guides.

FAQ

Is Claude Haiku 5.5 cheaper than DeepSeek V4.1 Flash?

For a typical 30-step coding agent run with caching, DeepSeek V4.1 Flash costs $0.09 and Claude Haiku 5.5 costs $0.12, so DeepSeek V4.1 Flash is 1.4x cheaper. Per 1M tokens, Claude Haiku 5.5 is $0.10 / $0.50 and DeepSeek V4.1 Flash is $0.30 / $1.20.

Which has the bigger context window?

Claude Haiku 5.5: 1,000,000 tokens. DeepSeek V4.1 Flash: 1,000,000 tokens.