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Router One

DeepSeek V4.1 Flash vs Gemini 3.8 Flash

Gemini 3.8 Flash is the lower-priced of the two on Router One — about 55% less on a 1M-input + 1M-output mix. DeepSeek V4.1 Flash offers 1M of context vs 1.05M for Gemini 3.8 Flash. DeepSeek V4.1 Flash answers on /v1/chat/completions, /v1/messages (Claude Code) and /v1/responses (Codex CLI); Gemini 3.8 Flash on /v1/chat/completions.

DeepSeek V4.1 Flash and Gemini 3.8 Flash compared on current per-token rates, context window, and capabilities — both callable through one OpenAI-compatible endpoint with per-request cost traces.

DeepSeek V4.1 Flash vs Gemini 3.8 Flash: rates, context window, and capabilities

SpecDeepSeek V4.1 FlashGemini 3.8 Flash
Input / 1M tokens$0.60$0.225
Output / 1M tokens$2.40$1.125
Cached input / 1M tokens$0.012$0.225
Context window1M1.05M
Detail pageDeepSeek V4.1 FlashGemini 3.8 Flash

What does 1M tokens cost on DeepSeek V4.1 Flash vs Gemini 3.8 Flash?

For a workload of 1M input plus 1M output tokens at current rates: DeepSeek V4.1 Flash comes to $3.00, Gemini 3.8 Flash comes to $1.35 — Gemini 3.8 Flash is about 55% cheaper on this mix. Real workloads skew heavily toward input tokens, so weigh the input rate by your own ratio; the cached-input row above is the posted catalog rate for that model.

Switch between DeepSeek V4.1 Flash and Gemini 3.8 Flash without changing code

Both models are behind the same OpenAI-compatible endpoint, so an A/B test is a one-string change — same key, same code, and every request traced with tokens, cost, and latency in the dashboard:

compare.sh
curl https://api.router.one/v1/chat/completions \
  -H "Authorization: Bearer sk-your-router-one-key" \
  -H "Content-Type: application/json" \
  -d '{"model": "deepseek-v4.1-flash", "messages": [{"role": "user", "content": "Hello"}]}'

# Same request, other model — change one string:
#   "model": "google/gemini-3.8-flash"

FAQ

Is DeepSeek V4.1 Flash cheaper than Gemini 3.8 Flash?

Input: DeepSeek V4.1 Flash $0.60 vs Gemini 3.8 Flash $0.225 / 1M tokens; Gemini 3.8 Flash has the lower rate. Output: DeepSeek V4.1 Flash $2.40 vs Gemini 3.8 Flash $1.125 / 1M tokens; Gemini 3.8 Flash has the lower rate. Total cost depends on the workload's input, output and cache usage. Rates change; the /models page is the live source of truth.

Can I switch between DeepSeek V4.1 Flash and Gemini 3.8 Flash without changing code?

Yes. Both are served through the same OpenAI-compatible endpoint, so switching is changing the model string in the request — the key, base URL, and request shape stay identical.

Where do these numbers come from?

Specs and prices on this page render from the live Router One catalog — the same data as the /models page — and refresh with it. Pricing methodology is documented on /pricing-methodology. Rates on this page were read from the live catalog on 2026-09-11 (UTC) and refresh within the hour.

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