DeepSeek V4 Pro vs Gemini 3.5 Flash: pricing and benchmarks
DeepSeek V4 Pro is 12% cheaper on input tokens ($1.32 vs $1.50 per 1M). DeepSeek V4 Pro is 56% cheaper on output tokens ($3.96 vs $9.00 per 1M). On our document Q&A workload (50,000 questions a month), DeepSeek V4 Pro costs $646.80 a month versus $870.00 for Gemini 3.5 Flash, 26% less. Roughly tied. DeepSeek V4 Pro scores 155.5 and Gemini 3.5 Flash scores 154.7 on the Epoch Capabilities Index, and their confidence intervals overlap.
Prices verified September 14, 2026.
Which should you choose?
Roughly tied. DeepSeek V4 Pro scores 155.5 and Gemini 3.5 Flash scores 154.7 on the Epoch Capabilities Index, and their confidence intervals overlap.
About even on FrontierMath (Tiers 1–3): 64.6% for DeepSeek V4 Pro and 62.8% for Gemini 3.5 Flash.
DeepSeek V4 Pro costs $1.98 per 1M tokens (3:1 input-to-output mix) vs $3.375 for Gemini 3.5 Flash, 41% less.
DeepSeek V4 Pro delivers equal or higher overall capability for 41% less.
Pricing and specs
| DeepSeek V4 Pro | Gemini 3.5 Flash | |
|---|---|---|
| Provider | DeepSeek | |
| API model ID | deepseek-v4-pro | gemini-3.5-flash |
| Input / 1M tokens | $1.32 | $1.50 |
| Cached input / 1M tokens | $0.044 | $0.15 |
| Output / 1M tokens | $3.96 | $9.00 |
| Long-context rates | — | — |
| Context window | 1M tokens | 1.05M tokens |
| Max output | 384K tokens | 66K tokens |
| Batch discount | — | 50% off |
Benchmarks
| DeepSeek V4 Pro | Gemini 3.5 Flash | |
|---|---|---|
| Epoch Capabilities Index | 155.5 | 154.7 |
| GPQA Diamond· Science reasoning | 88.9% | 90.4% |
| FrontierMath (Tiers 1–3)· Advanced math | 64.6% | 62.8% |
| SimpleQA Verified· Factual accuracy | 52.9% | 66.2% |
| ARC-AGI-2· Abstract reasoning | 61.3% | 72.1% |
| DeepSWE· Coding | — | 37.4% |
| APEX-Agents· Agentic work | — | — |
Source: Epoch AI, best recorded result per model (CC BY 4.0). A dash means no published score. See all benchmarks
Monthly cost for real workloads
| Workload | DeepSeek V4 Pro | Gemini 3.5 Flash | Difference |
|---|---|---|---|
Support chatbot 100,000 replies a month, ~1,500 input tokens (system prompt + history) and ~400 output tokens each. | $356.40 | $585.00 | DeepSeek V4 Pro 39% cheaper |
Document Q&A (RAG) 50,000 questions a month with ~8,000 tokens of retrieved context and ~600 output tokens each. | $646.80 | $870.00 | DeepSeek V4 Pro 26% cheaper |
Coding agent 10,000 agent steps a month, ~40,000 input tokens each (70% read from the prompt cache) and ~2,000 output tokens. | $249.92 | $402.00 | DeepSeek V4 Pro 38% cheaper |
Estimates use standard list prices and ignore cache-write surcharges. Different tokenizers can count the same text differently, so test with your own prompts.
DeepSeek V4 Pro vs Gemini 3.5 Flash cost calculator
- $646.80/mo$0.01 / request
- Gemini 3.5 FlashGoogle$870.00/mo$0.02 / request
Standard-tier list prices. Long-context rates apply automatically where the provider publishes a threshold. Excludes cache-write surcharges, taxes, batch and volume discounts.
DeepSeek V4 Pro pricing notes
DeepSeek’s larger V4 model with thinking and non-thinking modes and tool calls.
- Prices shown are peak rates. Off-peak rates are half: peak hours are 01:00–04:00 and 06:00–10:00 UTC, Monday to Friday.
- Vision input is not supported.
Gemini 3.5 Flash pricing notes
Google’s Gemini 3.5 Flash model, with thinking, tool use and a 1M-token context window.
- Output price includes thinking tokens.
- Context cache storage costs $1.00 per 1M tokens per hour.
- Priority inference costs 1.8x the standard rate.
Frequently asked questions
- Is DeepSeek V4 Pro cheaper than Gemini 3.5 Flash?
- DeepSeek V4 Pro is 12% cheaper on input tokens ($1.32 vs $1.50 per 1M). DeepSeek V4 Pro is 56% cheaper on output tokens ($3.96 vs $9.00 per 1M). On our document Q&A workload (50,000 questions a month), DeepSeek V4 Pro costs $646.80 a month versus $870.00 for Gemini 3.5 Flash, 26% less.
- Which is more capable, DeepSeek V4 Pro or Gemini 3.5 Flash?
- Roughly tied. DeepSeek V4 Pro scores 155.5 and Gemini 3.5 Flash scores 154.7 on the Epoch Capabilities Index, and their confidence intervals overlap.
- How much does DeepSeek V4 Pro cost per 1M tokens?
- DeepSeek V4 Pro costs $1.32 per 1M input tokens and $3.96 per 1M output tokens, and $0.044 per 1M cached input tokens on DeepSeek’s standard tier.
- How much does Gemini 3.5 Flash cost per 1M tokens?
- Gemini 3.5 Flash costs $1.50 per 1M input tokens and $9.00 per 1M output tokens, and $0.15 per 1M cached input tokens on Google’s standard tier.
- Which has the larger context window, DeepSeek V4 Pro or Gemini 3.5 Flash?
- Gemini 3.5 Flash has the larger context window: 1.05M tokens versus 1M for DeepSeek V4 Pro.