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Gemini 2.5 Pro vs Gemini 3.5 Flash

Side-by-side API economics and benchmarks. Per-1M input and output rates, context window, and verified metrics.

Tale of the tape

Head-to-head specs pulled from each model profile.

Metric Gemini 2.5 Pro Gemini 3.5 Flash
Input cost / 1M $1.25 $1.50
Output cost / 1M $10.00 $9.00
Context window 1,048,576 tokens 1,048,576 tokens
MMLU score

Cost verdict

Enter monthly input and output volumes to see total cost savings.

Gemini 2.5 Pro

Input: 1M × $1.25 = $1.25
Output: 1M × $10.00 = $10.00
Total
$11.25

Gemini 3.5 Flash

Input: 1M × $1.50 = $1.50
Output: 1M × $9.00 = $9.00
Total
$10.50

Total cost savings

$0.75

Gemini 3.5 Flash saves $0.75 per month vs the other model at this volume.

Model routing savings

Uses this page's verified rates. Gemini 2.5 Pro is the premium route (higher combined per-1M cost); Gemini 3.5 Flash handles routine traffic.

Premium model

Gemini 2.5 Pro

$1.25 in · $10.00 out / 1M

View profile →

Economical model

Gemini 3.5 Flash

$1.50 in · $9.00 out / 1M

View profile →

All premium

Gemini 2.5 Pro

$562.50

100% of input and output on the premium route

Routed stack

80%Gemini 3.5 Flash

Gemini 2.5 Pro

$532.50

Routine slice
$420.00
Premium slice
$112.50

Monthly savings

$30.00

5.3% lower

Rates pulled from this page's model database entries (gemini-2-5-pro, gemini-3-5-flash) — same per-1M input/output figures as Tale of the tape. Production routing needs quality gates and monitoring.

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