Claude Fable 5.1 vs GLM-5.3
Wins 7 of 7 areas
Coding · Agents · Reasoning · Facts · Math · Long documents · Following instructions
Wins 0 of 7 areas
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Claude Fable 5.1 is the stronger all-rounder.GLM-5.3 is cheaper.
Both rank among the ten best models we track in agents.
Scores updated · 44 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 software50Claude Fable 5.15 of 5 tests
- ReasoningHard problems that need careful thinking50Claude Fable 5.15 of 5 tests
- MathCompetition and research-level math30Claude Fable 5.13 of 3 tests
- AgentsCarrying out multi-step tasks on its own31Claude Fable 5.13 of 4 tests
- FactsGetting facts right instead of making them up21Claude Fable 5.12 of 3 tests
- Long documentsFinding answers in very long texts10Claude Fable 5.11 of 1 test
- Following instructionsDoing exactly what it is asked10Claude Fable 5.11 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.
GLM-5.3 costs 90% 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+58.5points ahead
- Answers hard knowledge questions correctlyAA-Omniscience · Accuracy+33.3points ahead
- Short factual questions, answered correctlySimpleQA Verified+29.8points ahead
Where GLM-5.3 pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+43points ahead
- Customer-service tasks in a simulated bankτ-Bench V3 · Banking+3.1points ahead
Every test, side by side
All 44 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingClaude Fable 5.1
- LMArena · WebDevClaude Fable 5.1 by 123 rating points17451622+123 rating
- Terminal-Bench 2.1Claude Fable 5.1 by 7.591.483.9+7.5
- LiveBench · CodingClaude Fable 5.1 by 7.486.479+7.4
- LiveBench · Agentic CodingClaude Fable 5.1 by 5.266.160.9+5.2
- SciCodeClaude Fable 5.1 by 4.163.159+4.1
AgentsClaude Fable 5.1
- Terminal-Bench 4.0Claude Fable 5.1 by 10.15241.9+10.1
- GDPValClaude Fable 5.1 by 5.262.757.5+5.2
- AA IT-Bench SREClaude Fable 5.1 by 3.449.546.1+3.4
- τ-Bench V3 · BankingGLM-5.3 by 3.147.250.3+3.1
ReasoningClaude Fable 5.1
- SimpleBenchClaude Fable 5.1 by 20.486.666.2+20.4
- Humanity's Last ExamClaude Fable 5.1 by 16.859.142.3+16.8
- CritPtClaude Fable 5.1 by 10.629.719.1+10.6
- LiveBench · ReasoningClaude Fable 5.1 by 5.991.785.8+5.9
- GPQA DiamondClaude Fable 5.1 by 293.791.7+2
FactsClaude Fable 5.1
- AA-Omniscience · Non-hallucinationGLM-5.3 by 4327.470.4+43
- AA-Omniscience · AccuracyClaude Fable 5.1 by 33.367.233.9+33.3
- SimpleQA VerifiedClaude Fable 5.1 by 29.870.841+29.8
MathClaude Fable 5.1
- FrontierMath Tier 4Claude Fable 5.1 by 58.587.829.3+58.5
- FrontierMath Tiers 1-3 (v2)Claude Fable 5.1 by 21.490.268.8+21.4
- LiveBench · MathematicsClaude Fable 5.1 by 9.19787.9+9.1
Following instructionsClaude Fable 5.1
- LiveBench · Instruction FollowingClaude Fable 5.1 by 3.77369.3+3.7
Other results22 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.
- Program BenchClaude Fable 5.1 by 68.687.619+68.6
- HLE-DiamondClaude Fable 5.1 by 42.260.117.9+42.2
- Terminal-Bench-Science 0.1Claude Fable 5.1 by 33.843.39.5+33.8
- AA-OmniscienceClaude Fable 5.1 by 29.243.514.3+29.2
- CritPt v2 HardClaude Fable 5.1 by 1952.533.5+19
- GDP (Surge AI)Claude Fable 5.1 by 1526.211.2+15
- Terminal-Bench 4.0Claude Fable 5.1 by 1455.841.8+14
- livebench_data_analysisClaude Fable 5.1 by 10.180.370.2+10.1
- PostTrain Bench v1.2Claude Fable 5.1 by 10.144.634.5+10.1
- livebench_languageClaude Fable 5.1 by 9.689.579.9+9.6
- AA IntelligenceClaude Fable 5.1 by 8.653.444.8+8.6
- Artificial Analysis Coding IndexClaude Fable 5.1 by 6.881.674.8+6.8
- GDPval-AA v2Claude Fable 5.1 by 66 rating points18351769+66 rating
- HealthBench ProfessionalClaude Fable 5.1 by 557.852.8+5
- Toolathlon VerifiedClaude Fable 5.1 by 4.877.873+4.8
- AA Agentic IndexClaude Fable 5.1 by 4.65853.4+4.6
- HiL-Bench (Tools-allowed)Claude Fable 5.1 by 3.261.558.3+3.2
- SWE Marathon v1.1Claude Fable 5.1 by 3.145.642.5+3.1
- HealthBenchClaude Fable 5.1 by 2.757.254.5+2.7
- HLE (with tools)Claude Fable 5.1 by 2.56562.5+2.5
- DeepSWE 1.1tie67.466.9tie
- PostTrainBenchtie40.239.8tie
Questions people ask
Which is better, Claude Fable 5.1 or GLM-5.3?
Claude Fable 5.1 wins all seven areas where both have results: coding, agents, reasoning, facts, math, long documents and following instructions. GLM-5.3 wins none, but costs 90% less.
Which is better for coding?
Claude Fable 5.1. It wins 5 of the 5 coding tests both models report; GLM-5.3 wins none.
Which is cheaper?
Claude Fable 5.1 costs $10.00 per million input tokens and $50.00 per million output tokens; GLM-5.3 costs $1.40 and $4.40. That makes GLM-5.3 about 90% cheaper for the same work.
How do you compare the two?
We use the 44 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 22 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.