DeepSeek-R1 vs Gemini 2.5 Flash: Detailed Comparison

Choosing between DeepSeek-R1 (DeepSeek) and Gemini 2.5 Flash (Google) comes down to three things: per-token pricing, context window, and which capability matters most for your workload. DeepSeek-R1 costs $0.55/M input vs $0.30/M for Gemini 2.5 Flash; context windows are 128K vs 1.0M tokens. Detailed breakdown below.

Side-by-side specs

SpecDeepSeek-R1Gemini 2.5 Flash
ProviderDeepSeekGoogle
Released2025-01-202025-04-09
Input price $0.55/M $0.30/M
Output price $2.19/M $2.50/M
Cached input $0.1400/M $0.0750/M
Context window 128K 1.0M
Max output 32K 66K
Modalities text text image audio video
Tokenizer deepseek gemini

Capability matrix

CapabilityDeepSeek-R1Gemini 2.5 Flash
json mode Yes Yes
streaming Yes Yes
reasoning Yes No
function calling No Yes
vision No Yes
audio No Yes
video No Yes

Benchmark comparison

Higher is better for all benchmarks shown.

BenchmarkCategoryDeepSeek-R1Gemini 2.5 FlashΔ
GPQA Diamond reasoning 71.5
MATH math 97.3
AIME 2025 math 79.8

Per-call cost on typical workloads

Workload (in/out tokens)DeepSeek-R1Gemini 2.5 FlashCheaper by
Standard chat (1K / 500) $0.001645 $0.001550 Gemini 2.5 Flash by $0.000095
RAG (4K / 500) $0.003295 $0.002450 Gemini 2.5 Flash by $0.000845
Long doc (20K / 1K) $0.013190 $0.008500 Gemini 2.5 Flash by $0.004690
Very long context (100K / 2K) $0.058285 $0.033750 Gemini 2.5 Flash by $0.024535

When to choose DeepSeek-R1 over Gemini 2.5 Flash

  • Supports reasoning — Gemini 2.5 Flash does not.

When to choose Gemini 2.5 Flash over DeepSeek-R1

  • Per-token input cost is 45% lower than DeepSeek-R1.
  • Larger context window (1.0M vs 128K).
  • Supports function calling — DeepSeek-R1 does not.
  • Supports vision — DeepSeek-R1 does not.
  • Supports audio — DeepSeek-R1 does not.
  • Supports video — DeepSeek-R1 does not.

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