A.X-K2 vs Claude Fable 5
Wins 0 of 5 areas
—
Wins 4 of 5 areas
Coding · Agents · Reasoning · Long documents
Claude Fable 5 is the stronger all-rounder.
Scores updated · 15 tests both models report · How we compare
Where each one wins
Tests won in each of the five 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.
- AgentsCarrying out multi-step tasks on its own03Claude Fable 53 of 3 tests
- ReasoningHard problems that need careful thinking03Claude Fable 53 of 3 tests
- CodingWriting and fixing software02Claude Fable 52 of 2 tests
- Long documentsFinding answers in very long texts01Claude Fable 51 of 1 test
- FactsGetting facts right instead of making them up11Even1 each
Long documents rests on a single test.
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.
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
- Answers hard knowledge questions correctlyAA-Omniscience · Accuracy+46.8points ahead
- Command-line tasks in a real terminalTerminal-Bench 2.1+45.6points ahead
- Real work tasks from 44 professionsGDPVal+32.4points ahead
Where A.X-K2 pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+30.6points ahead
Every test, side by side
All 15 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 45.63984.6+45.6
- SciCodeClaude Fable 5 by 204161+20
AgentsClaude Fable 5
- Terminal-Bench 4.0Claude Fable 5 by 42.4042.4+42.4
- GDPValClaude Fable 5 by 32.423.255.6+32.4
- τ-Bench V3 · BankingClaude Fable 5 by 2216.138.1+22
ReasoningClaude Fable 5
- Humanity's Last ExamClaude Fable 5 by 25.929.655.5+25.9
- CritPtClaude Fable 5 by 19.78.928.6+19.7
- GPQA DiamondClaude Fable 5 by 6.985.792.6+6.9
FactsEven
- AA-Omniscience · AccuracyClaude Fable 5 by 46.818.665.3+46.8
- AA-Omniscience · Non-hallucinationA.X-K2 by 30.66736.4+30.6
Other results4 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 51.5-8.243.3+51.5
- Artificial Analysis Coding IndexClaude Fable 5 by 37.738.876.5+37.7
- AA IntelligenceClaude Fable 5 by 28.121.549.6+28.1
- AA Agentic IndexClaude Fable 5 by 25.325.751+25.3
Questions people ask
Which is better, A.X-K2 or Claude Fable 5?
Claude Fable 5 wins four of the five areas where both have results: coding, agents, reasoning and long documents. A.X-K2 wins none. They are level on facts.
Which is better for coding?
Claude Fable 5. It wins 2 of the 2 coding tests both models report; A.X-K2 wins none.
How do you compare the two?
We use the 15 benchmark tests both models have published scores on. The verdict counts the 11 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 4 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.