LLM Cost Calculator

DeepSeek V4 Pro vs Gemini 3.5 Flash — LLM API Cost Comparison

Compare DeepSeek V4 Pro (DeepSeek) vs Gemini 3.5 Flash (Google) on cost per million tokens, context window, and monthly spend.

Prices verified 2026-06-06 · Pricing may change — use the calculator for current estimates

DeepSeek
DeepSeek V4 Pro
Current
Input
$0.44/1M tokens
Output
$0.87/1M tokens
Context
1M tokens
Released
2026-03

DeepSeek flagship; 1M context; promo 75% off ($0.435/$0.87) until May 31 2026

Google
Gemini 3.5 Flash
Current
Input
$1.5/1M tokens
Output
$9/1M tokens
Context
1M tokens
Released
2026-05

Latest Gemini; frontier intelligence + superior search & grounding

Monthly Cost by Usage Tier (70% input / 30% output ratio)

UsageDeepSeek V4 ProGemini 3.5 FlashCheaper by
Light (1M tokens)$0.569$3.75DeepSeek V4 Pro (85%)
Moderate (10M tokens)$5.69$37.50DeepSeek V4 Pro (85%)
Heavy (100M tokens)$56.90$375DeepSeek V4 Pro (85%)
Very Heavy (1B tokens)$569$3,750DeepSeek V4 Pro (85%)

Frequently Asked Questions

Which is cheaper — DeepSeek V4 Pro or Gemini 3.5 Flash?

For input tokens, DeepSeek V4 Pro is cheaper at $0.44/1M tokens — 3.4× less than $1.5/1M. For output tokens, DeepSeek V4 Pro wins at $0.87/1M vs $9/1M. At heavy workloads (100M tokens/month), the cost difference can be significant.

What is the context window difference between DeepSeek V4 Pro and Gemini 3.5 Flash?

DeepSeek V4 Pro supports 1,000,000 tokens per request; Gemini 3.5 Flash supports 1,000,000 tokens. DeepSeek V4 Pro wins on context length, making it better for long documents, large codebases, or extended conversations without chunking.

When should I choose DeepSeek V4 Pro over Gemini 3.5 Flash?

Choose DeepSeek V4 Pro (DeepSeek) if you prefer DeepSeek's ecosystem, tooling, or reliability track record. DeepSeek flagship; 1M context; promo 75% off ($0.435/$0.87) until May 31 2026. Choose Gemini 3.5 Flash (Google) if Latest Gemini; frontier intelligence + superior search & grounding. the price/performance fits your workload better. Use this calculator to find the break-even point for your exact token volume.

How much does 1 billion tokens cost on DeepSeek V4 Pro vs Gemini 3.5 Flash?

At 700M input + 300M output tokens (1B total): DeepSeek V4 Pro costs $569; Gemini 3.5 Flash costs $3750. The difference is $3181/billion tokens at this 70/30 input/output ratio.