Claude Fable 5 vs Step 3.7 Flash
Wins 6 of 7 areas
Coding · Agents · Reasoning · Facts · Images and charts · Long documents
Wins 1 of 7 areas
Following instructions
Claude Fable 5 is the stronger all-rounder.Step 3.7 Flash is cheaper and better at following instructions.
Scores updated · 20 tests both models report · How we compare
Where each one wins
Tests won in each of the seven areas where both have results. 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 software40Claude Fable 54 of 4 tests
- AgentsCarrying out multi-step tasks on its own30Claude Fable 53 of 3 tests
- ReasoningHard problems that need careful thinking30Claude Fable 53 of 3 tests
- FactsGetting facts right instead of making them up20Claude Fable 52 of 2 tests
- Images and chartsUnderstanding pictures, charts and video10Claude Fable 51 of 1 test
- Long documentsFinding answers in very long texts10Claude Fable 51 of 1 test
- Following instructionsDoing exactly what it is asked01Step 3.7 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.
Step 3.7 Flash costs 98% 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 pulls ahead
- Command-line tasks in a real terminalTerminal-Bench 2.1+45.3points ahead
- Answers hard knowledge questions correctlyAA-Omniscience · Accuracy+39.6points ahead
- Real work tasks from 44 professionsGDPVal+37.6points ahead
Where Step 3.7 Flash pulls ahead
- Follows unfamiliar, precisely checkable instructionsIFBench+3.8points ahead
Every test, side by side
All 20 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingClaude Fable 5
- Terminal-Bench 2.1Claude Fable 5 by 45.384.639.3+45.3
- Terminal-Bench HardClaude Fable 5 by 27.362.935.6+27.3
- SWE-bench ProClaude Fable 5 by 23.78056.3+23.7
- SciCodeClaude Fable 5 by 17.16143.9+17.1
AgentsClaude Fable 5
- GDPValClaude Fable 5 by 37.655.618+37.6
- AA ApexAgentsClaude Fable 5 by 28.543.314.8+28.5
- τ-Bench V3 · BankingClaude Fable 5 by 26.138.112+26.1
ReasoningClaude Fable 5
- Humanity's Last ExamClaude Fable 5 by 34.155.521.4+34.1
- CritPtClaude Fable 5 by 26.328.62.3+26.3
- GPQA DiamondClaude Fable 5 by 11.792.680.9+11.7
FactsClaude Fable 5
- AA-Omniscience · AccuracyClaude Fable 5 by 39.665.325.8+39.6
- AA-Omniscience · Non-hallucinationClaude Fable 5 by 21.436.415+21.4
Images and chartsClaude Fable 5
- MMMU-ProClaude Fable 5 by 8.984.275.3+8.9
Following instructionsStep 3.7 Flash
- IFBenchStep 3.7 Flash by 3.863.567.3+3.8
Other results5 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.
- AA-OmniscienceClaude Fable 5 by 80.643.3-37.3+80.6
- Artificial Analysis Coding IndexClaude Fable 5 by 36.976.539.6+36.9
- AA IntelligenceClaude Fable 5 by 30.149.619.5+30.1
- AA Agentic IndexClaude Fable 5 by 29.35121.7+29.3
- τ²-Bench Telecom (AA run)tie98.598.5tie
Questions people ask
Which is better, Claude Fable 5 or Step 3.7 Flash?
Claude Fable 5 wins six of the seven areas where both have results: coding, agents, reasoning, facts, images and charts and long documents. Step 3.7 Flash wins following instructions, and costs 98% less.
Which is better for coding?
Claude Fable 5. It wins 4 of the 4 coding tests both models report; Step 3.7 Flash wins none.
Which is cheaper?
Claude Fable 5 costs $10.00 per million input tokens and $50.00 per million output tokens; Step 3.7 Flash costs $0.20 and $1.15. That makes Step 3.7 Flash about 98% cheaper for the same work.
How do you compare the two?
We use the 20 benchmark tests both models have published scores on. The verdict counts the 15 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 5 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.