DeepSeek-V4-Pro vs Gemini 3.1 Pro Preview

Compare DeepSeek-V4-Pro and Gemini 3.1 Pro Preview on the metrics that decide an agent workload.

MetricDeepSeek-V4-ProGemini 3.1 Pro Preview
ProviderFireworks AIGoogle Gemini
Input / 1M$1.74$2.00
Output / 1M$3.48$12.00
Cache read / 1M$0.14 (−92%)$0.20 (−90%)
Reuse-adj @55%$1.52$3.76
Context1M1M
Cache capture80%82%
Warm TTFT130ms (−63%)360ms (−56%)
Quality index8894

Teal marks the better value in each row. Reuse-adjusted assumes 55% prefix reuse and a 25% output share.

Pick DeepSeek-V4-Pro when

Pick DeepSeek-V4-Pro when it is cheaper once prefix reuse is priced in, it answers faster on warm cache hits, it is open-weights for on-prem and regulated lanes.

Pick Gemini 3.1 Pro Preview when

Pick Gemini 3.1 Pro Preview when it scores higher on the composite quality index, it carries the larger 1M context window, it captures more of the available reuse.

Verdict

Gemini 3.1 Pro Preview leads on quality while DeepSeek-V4-Pro leads on reuse-adjusted cost. Send latency- and budget-sensitive volume to DeepSeek-V4-Pro and reserve Gemini 3.1 Pro Preview for the hard requests. Zumik's aliases route between them automatically under policy.

DeepSeek-V4-Pro vs Gemini 3.1 Pro Preview, answered.

Is DeepSeek-V4-Pro or Gemini 3.1 Pro Preview cheaper?

At 55% prefix reuse, DeepSeek-V4-Pro blends to about $1.52 per 1M tokens and Gemini 3.1 Pro Preview to about $3.76. DeepSeek-V4-Pro is cheaper on that basis.

Which has the larger context window?

Gemini 3.1 Pro Preview has the larger window: 1M vs 1M tokens.

Which captures more reuse?

Gemini 3.1 Pro Preview shows higher measured cache capture (82% vs 80%) in the Zumik corpus.

Let an alias pick for you.

Route to whichever model wins under current policy automatically. Zumik resolves the alias to the best fit per request, so you never hard-code a loser.