Claude Fable 5 vs Grok 4.3
Wins 6 of 8 areas
Coding · Agents · Reasoning · Images and charts · Math · Long documents
Wins 0 of 8 areas
—
Claude Fable 5 is the stronger all-rounder.Grok 4.3 is cheaper.
Scores updated · 30 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 56 of 6 tests
- AgentsCarrying out multi-step tasks on its own40Claude Fable 54 of 4 tests
- ReasoningHard problems that need careful thinking40Claude Fable 54 of 4 tests
- Images and chartsUnderstanding pictures, charts and video20Claude Fable 52 of 2 tests
- MathCompetition and research-level math10Claude Fable 51 of 1 test
- Long documentsFinding answers in very long texts10Claude Fable 51 of 1 test
- FactsGetting facts right instead of making them up11Even1 each
- Following instructionsDoing exactly what it is asked11Even1 each
Math and long documents 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.
Grok 4.3 costs 94% 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+44.9points ahead
- Fixes real GitHub issues, working as an agentLiveBench · Agentic Coding+43.7points ahead
- Real work tasks from 44 professionsGDPVal+33.6points ahead
Where Grok 4.3 pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+37.8points ahead
- Follows unfamiliar, precisely checkable instructionsIFBench+17.8points ahead
Every test, side by side
All 30 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 44.984.639.7+44.9
- LiveBench · Agentic CodingClaude Fable 5 by 43.762.218.5+43.7
- LMArena · WebDevClaude Fable 5 by 268 rating points16251357+268 rating
- Terminal-Bench HardClaude Fable 5 by 2562.937.9+25
- LiveBench · CodingClaude Fable 5 by 16.18669.9+16.1
- SciCodeClaude Fable 5 by 12.76148.3+12.7
AgentsClaude Fable 5
- Terminal-Bench 4.0Claude Fable 5 by 42.442.40+42.4
- GDPValClaude Fable 5 by 33.655.622+33.6
- AA ApexAgentsClaude Fable 5 by 26.343.317+26.3
- τ-Bench V3 · BankingClaude Fable 5 by 25.738.112.4+25.7
ReasoningClaude Fable 5
- CritPtClaude Fable 5 by 20.628.68+20.6
- LiveBench · ReasoningClaude Fable 5 by 18.989.770.8+18.9
- Humanity's Last ExamClaude Fable 5 by 18.355.537.2+18.3
- GPQA DiamondClaude Fable 5 by 2.592.690.1+2.5
FactsEven
- AA-Omniscience · Non-hallucinationGrok 4.3 by 37.836.474.2+37.8
- AA-Omniscience · AccuracyClaude Fable 5 by 30.665.334.8+30.6
Images and chartsClaude Fable 5
- LMArena · VisionClaude Fable 5 by 96 rating points13251229+96 rating
- MMMU-ProClaude Fable 5 by 6.184.278.1+6.1
Following instructionsEven
- IFBenchGrok 4.3 by 17.863.581.3+17.8
- LiveBench · Instruction FollowingClaude Fable 5 by 1375.862.8+13
Other results8 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.
- Artificial Analysis Coding IndexClaude Fable 5 by 34.376.542.2+34.3
- AA Agentic IndexClaude Fable 5 by 33.85117.2+33.8
- AA-OmniscienceClaude Fable 5 by 25.343.318+25.3
- AA IntelligenceClaude Fable 5 by 24.749.624.9+24.7
- livebench_data_analysisClaude Fable 5 by 24.780.555.8+24.7
- Finance Agent v2Claude Fable 5 by 18.656.337.7+18.6
- livebench_languageClaude Fable 5 by 17.190.773.6+17.1
- τ²-Bench Telecom (AA run)tie98.597.7tie
Questions people ask
Which is better, Claude Fable 5 or Grok 4.3?
Claude Fable 5 wins six of the eight areas we test: coding, agents, reasoning, images and charts, math and long documents. Grok 4.3 wins none, but costs 94% less. They are level on facts and following instructions.
Which is better for coding?
Claude Fable 5. It wins 6 of the 6 coding tests both models report; Grok 4.3 wins none.
Which is cheaper?
Claude Fable 5 costs $10.00 per million input tokens and $50.00 per million output tokens; Grok 4.3 costs $1.25 and $2.50. That makes Grok 4.3 about 94% cheaper for the same work.
How do you compare the two?
We use the 30 benchmark tests both models have published scores on. The verdict counts the 22 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 8 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.