Claude Fable 5.1 vs Gemini 3.5 Flash
Wins 7 of 8 areas
Coding · Agents · Reasoning · Facts · Images and charts · Math · Long documents
Wins 1 of 8 areas
Following instructions
Claude Fable 5.1 is the stronger all-rounder.Gemini 3.5 Flash is cheaper and better at following instructions.
Scores updated · 38 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 software60Claude Fable 5.16 of 6 tests
- ReasoningHard problems that need careful thinking60Claude Fable 5.16 of 6 tests
- AgentsCarrying out multi-step tasks on its own40Claude Fable 5.14 of 4 tests
- MathCompetition and research-level math30Claude Fable 5.13 of 3 tests
- FactsGetting facts right instead of making them up21Claude Fable 5.12 of 3 tests
- Images and chartsUnderstanding pictures, charts and video10Claude Fable 5.11 of 1 test
- Long documentsFinding answers in very long texts10Claude Fable 5.11 of 1 test
- Following instructionsDoing exactly what it is asked01Gemini 3.5 Flash1 of 1 test
Images and charts, 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 83% 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 Claude Fable 5.1 pulls ahead
- Extremely hard research-level math problemsFrontierMath Tier 4+61points ahead
- Complex command-line tasks across many fieldsTerminal-Bench 4.0+45.4points ahead
- Real work tasks from 44 professionsGDPVal+27.6points ahead
Where Gemini 3.5 Flash pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+10.4points ahead
- Follows detailed instructions exactlyLiveBench · Instruction Following+2.6points ahead
Every test, side by side
All 38 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingClaude Fable 5.1
- SWE-bench ProClaude Fable 5.1 by 26.181.255.1+26.1
- LMArena · WebDevClaude Fable 5.1 by 243 rating points17421499+243 rating
- LiveBench · Agentic CodingClaude Fable 5.1 by 17.166.149+17.1
- Terminal-Bench 2.1Claude Fable 5.1 by 12.791.478.7+12.7
- SciCodeClaude Fable 5.1 by 9.263.153.9+9.2
- LiveBench · CodingClaude Fable 5.1 by 8.286.478.2+8.2
AgentsClaude Fable 5.1
- Terminal-Bench 4.0Claude Fable 5.1 by 45.4526.6+45.4
- GDPValClaude Fable 5.1 by 27.662.735.1+27.6
- τ-Bench V3 · BankingClaude Fable 5.1 by 1547.232.2+15
- AA IT-Bench SREClaude Fable 5.1 by 9.249.540.3+9.2
ReasoningClaude Fable 5.1
- ARC-AGI-2Claude Fable 5.1 by 17.99072.1+17.9
- CritPtClaude Fable 5.1 by 16.629.713.1+16.6
- Humanity's Last ExamClaude Fable 5.1 by 16.459.142.7+16.4
- SimpleBenchClaude Fable 5.1 by 9.986.676.7+9.9
- LiveBench · ReasoningClaude Fable 5.1 by 9.791.782+9.7
- GPQA DiamondClaude Fable 5.1 by 1.593.792.2+1.5
FactsClaude Fable 5.1
- AA-Omniscience · AccuracyClaude Fable 5.1 by 15.867.251.4+15.8
- AA-Omniscience · Non-hallucinationGemini 3.5 Flash by 10.427.437.8+10.4
- SimpleQA VerifiedClaude Fable 5.1 by 4.670.866.2+4.6
Images and chartsClaude Fable 5.1
- LMArena · VisionClaude Fable 5.1 by 11 rating points13191308+11 rating
MathClaude Fable 5.1
- FrontierMath Tier 4Claude Fable 5.1 by 6187.826.8+61
- FrontierMath Tiers 1-3 (v2)Claude Fable 5.1 by 27.490.262.8+27.4
- LiveBench · MathematicsClaude Fable 5.1 by 8.89788.2+8.8
Following instructionsGemini 3.5 Flash
- LiveBench · Instruction FollowingGemini 3.5 Flash by 2.67375.6+2.6
Other results13 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.
- GDPval-AA v2Claude Fable 5.1 by 504 rating points18531349+504 rating
- GDPval-AA v2 EloClaude Fable 5.1 by 486 rating points18351349+486 rating
- HiL-Bench (Tools-allowed)Claude Fable 5.1 by 33.861.527.7+33.8
- AA Agentic IndexClaude Fable 5.1 by 30.75827.3+30.7
- DeepSWE 1.1Claude Fable 5.1 by 30.467.437+30.4
- AA-OmniscienceClaude Fable 5.1 by 22.343.521.2+22.3
- AA IntelligenceClaude Fable 5.1 by 20.853.432.6+20.8
- livebench_data_analysisClaude Fable 5.1 by 15.480.364.9+15.4
- Artificial Analysis Coding IndexClaude Fable 5.1 by 11.581.670.1+11.5
- GDPval-AA (Elo)Claude Fable 5.1 by 79 rating points17351656+79 rating
- ARC-AGI-1Claude Fable 5.1 by 597.592.5+5
- livebench_languageClaude Fable 5.1 by 4.989.584.6+4.9
- LVBenchClaude Fable 5.1 by 3.479.776.3+3.4
Questions people ask
Which is better, Claude Fable 5.1 or Gemini 3.5 Flash?
Claude Fable 5.1 wins seven of the eight areas we test: coding, agents, reasoning, facts, images and charts, math and long documents. Gemini 3.5 Flash wins following instructions, and costs 83% less.
Which is better for coding?
Claude Fable 5.1. It wins 6 of the 6 coding tests both models report; Gemini 3.5 Flash wins none.
Which is cheaper?
Claude Fable 5.1 costs $10.00 per million input tokens and $50.00 per million output tokens; Gemini 3.5 Flash costs $1.50 and $9.00. That makes Gemini 3.5 Flash about 83% cheaper for the same work.
How do you compare the two?
We use the 38 benchmark tests both models have published scores on. The verdict counts the 25 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 13 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.