Gemini 2.5 Flash vs DeepSeek Flash (V4.1)

DeepSeek Flash (V4.1) is the cheaper of the two across every workload shape tested below. Headline rates are $0.3 in / $2.5 out for Gemini 2.5 Flash versus $0.3 in / $1.2 out for DeepSeek Flash (V4.1), per million tokens.

Real monthly cost, three workloads

Workload Gemini 2.5 Flash DeepSeek Flash (V4.1) Cheaper
Support chatbot
1.5k in / 400 out · 100k req/mo · 30% cached
$132.85 $79.77 DeepSeek Flash (V4.1) (1.7× cheaper)
RAG / doc Q&A
12k in / 700 out · 50k req/mo · 60% cached
$170.30 $116.16 DeepSeek Flash (V4.1) (1.5× cheaper)
Coding agent
25k in / 2.5k out · 20k req/mo · 80% cached
$167.00 $92.40 DeepSeek Flash (V4.1) (1.8× cheaper)

Costs include prompt caching at the stated hit rate and per-model tokenizer correction. Adjust for your own traffic →

Specifications side by side

Gemini 2.5 Flash DeepSeek Flash (V4.1)
Provider Google DeepSeek
Input / M tokens $0.3 $0.3
Output / M tokens $2.5 $1.2
Cached input $0.03 $0.006
Context window 1000K 1000K
Batch discount −50% —
Tokenizer factor ×1 ×1
Min prefix to cache — —
Announced retirement — —

Which should you pick?

On cost alone, DeepSeek Flash (V4.1) wins every workload shape above.

Full detail: Gemini 2.5 Flash · DeepSeek Flash (V4.1)

All figures verified 2026-10-05 against official provider documentation. Fields a provider does not publish are shown as “—” rather than estimated.