Claude Sonnet 4.5 vs Gemini 3.5 Flash
Wins 0 of 8 areas
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Wins 8 of 8 areas
Coding · Agents · Reasoning · Facts · Images and charts · Math · Long documents · Following instructions
Gemini 3.5 Flash is the stronger all-rounder.
Scores updated · 34 tests both models report · How we compare
Where each one wins
Tests won in each of the eight areas we test. Each piece is one test, so a longer bar means more evidence; grey means the two scored within a point of each other.
- CodingWriting and fixing software05Gemini 3.5 Flash5 of 5 tests
- AgentsCarrying out multi-step tasks on its own05Gemini 3.5 Flash5 of 5 tests
- ReasoningHard problems that need careful thinking05Gemini 3.5 Flash5 of 5 tests
- Images and chartsUnderstanding pictures, charts and video02Gemini 3.5 Flash2 of 2 tests
- MathCompetition and research-level math02Gemini 3.5 Flash2 of 2 tests
- FactsGetting facts right instead of making them up12Gemini 3.5 Flash2 of 3 tests
- Long documentsFinding answers in very long texts01Gemini 3.5 Flash1 of 1 test
- Following instructionsDoing exactly what it is asked01Gemini 3.5 Flash1 of 1 test
Long documents and following instructions rest on a single test each.
What it costs
Prices per million tokens, roughly 750,000 words. The bars show the cost of a million tokens read plus a million written.
Gemini 3.5 Flash costs 42% less for the same work.
The biggest differences
The tests each model wins by the widest margin, up to three each. Scores are out of 100.
Where Gemini 3.5 Flash pulls ahead
- Abstract visual puzzles that people can solveARC-AGI-2+58.5points ahead
- Multi-step tasks using many real software toolsMCP Atlas+39.8points ahead
- Unpublished advanced math problemsFrontierMath Tiers 1-3 (v2)+38.9points ahead
Where Claude Sonnet 4.5 pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+13.1points ahead
Every test, side by side
All 34 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingGemini 3.5 Flash
- Terminal-Bench 2.1Gemini 3.5 Flash by 22.955.878.7+22.9
- SWE-bench ProGemini 3.5 Flash by 11.543.655.1+11.5
- LMArena · WebDevGemini 3.5 Flash by 106 rating points13931499+106 rating
- SciCodeGemini 3.5 Flash by 8.245.753.9+8.2
- Terminal-Bench HardGemini 3.5 Flash by 5.335.640.9+5.3
AgentsGemini 3.5 Flash
- MCP AtlasGemini 3.5 Flash by 39.843.883.6+39.8
- OSWorld-VerifiedGemini 3.5 Flash by 1761.478.4+17
- GDPValGemini 3.5 Flash by 14.720.535.2+14.7
- τ-Bench V3 · BankingGemini 3.5 Flash by 7.724.532.2+7.7
- Terminal-Bench 4.0Gemini 3.5 Flash by 6.606.6+6.6
ReasoningGemini 3.5 Flash
- ARC-AGI-2Gemini 3.5 Flash by 58.513.672.1+58.5
- Humanity's Last ExamGemini 3.5 Flash by 24.917.842.7+24.9
- SimpleBenchGemini 3.5 Flash by 22.454.376.7+22.4
- CritPtGemini 3.5 Flash by 121.113.1+12
- GPQA DiamondGemini 3.5 Flash by 8.883.492.2+8.8
FactsGemini 3.5 Flash
- SimpleQA VerifiedGemini 3.5 Flash by 35.530.766.2+35.5
- AA-Omniscience · AccuracyGemini 3.5 Flash by 18.532.951.4+18.5
- AA-Omniscience · Non-hallucinationClaude Sonnet 4.5 by 13.150.937.8+13.1
Images and chartsGemini 3.5 Flash
- CharXiv (RQ)Gemini 3.5 Flash by 1767.284.2+17
- MMMU-ProGemini 3.5 Flash by 15.668.784.3+15.6
MathGemini 3.5 Flash
- FrontierMath Tiers 1-3 (v2)Gemini 3.5 Flash by 38.923.962.8+38.9
- FrontierMath Tier 4Gemini 3.5 Flash by 24.42.426.8+24.4
Following instructionsGemini 3.5 Flash
- IFBenchGemini 3.5 Flash by 1957.376.3+19
Other results10 tests, not counted
Tests outside the eight areas. They are not counted above: several are summary scores built from other tests, or the same test under another name.
- ARC-AGI-1Gemini 3.5 Flash by 28.863.792.5+28.8
- Terminal-Bench 2.0Gemini 3.5 Flash by 26.25076.2+26.2
- AA-OmniscienceGemini 3.5 Flash by 21.3-0.121.2+21.3
- Artificial Analysis Coding IndexGemini 3.5 Flash by 1852.170.1+18
- τ²-Bench Telecom (AA run)Gemini 3.5 Flash by 17.278.195.3+17.2
- ToolathlonGemini 3.5 Flash by 15.54156.5+15.5
- matharena_visual_math_overallGemini 3.5 Flash by 14.175.889.9+14.1
- AA IntelligenceGemini 3.5 Flash by 11.920.732.6+11.9
- frontiermath_tier_4_v1Gemini 3.5 Flash by 10.44.214.6+10.4
- AA Agentic IndexGemini 3.5 Flash by 9.817.527.3+9.8
Questions people ask
Which is better, Claude Sonnet 4.5 or Gemini 3.5 Flash?
Gemini 3.5 Flash wins all eight areas we test: coding, agents, reasoning, facts, images and charts, math, long documents and following instructions. Claude Sonnet 4.5 wins none.
Which is better for coding?
Gemini 3.5 Flash. It wins 5 of the 5 coding tests both models report; Claude Sonnet 4.5 wins none.
Which is cheaper?
Claude Sonnet 4.5 costs $3.00 per million input tokens and $15.00 per million output tokens; Gemini 3.5 Flash costs $1.50 and $9.00. That makes Gemini 3.5 Flash about 42% cheaper for the same work.
How do you compare the two?
We use the 34 benchmark tests both models have published scores on. The verdict counts the 24 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 10 are listed but not counted, because several are summary scores or repeat a test. Each score is the one shown on the model's own page.