Claude Fable 5 vs GLM-5.3
Wins 6 of 7 areas
Coding · Reasoning · Facts · Math · Long documents · Following instructions
Wins 1 of 7 areas
Agents
Claude Fable 5 is the stronger all-rounder.GLM-5.3 is cheaper and better at agents.
Both rank among the ten best models we track in agents.
Scores updated · 38 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.
- ReasoningHard problems that need careful thinking40Claude Fable 54 of 5 tests · 1 tie
- CodingWriting and fixing software30Claude Fable 53 of 5 tests · 2 ties
- MathCompetition and research-level math30Claude Fable 53 of 3 tests
- FactsGetting facts right instead of making them up21Claude Fable 52 of 3 tests
- Long documentsFinding answers in very long texts10Claude Fable 51 of 1 test
- Following instructionsDoing exactly what it is asked10Claude Fable 51 of 1 test
- AgentsCarrying out multi-step tasks on its own02GLM-5.32 of 3 tests · 1 tie
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 three tests each model wins by the widest margin. Scores are out of 100.
Where Claude Fable 5 pulls ahead
- Extremely hard research-level math problemsFrontierMath Tier 4+60.9points ahead
- Answers hard knowledge questions correctlyAA-Omniscience · Accuracy+31.5points ahead
- Short factual questions, answered correctlySimpleQA Verified+29.7points ahead
Where GLM-5.3 pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+34points ahead
- Customer-service tasks in a simulated bankτ-Bench V3 · Banking+12.2points ahead
- Real work tasks from 44 professionsGDPVal+1.9points 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
- LiveBench · CodingClaude Fable 5 by 78679+7
- SciCodeClaude Fable 5 by 26159+2
- LiveBench · Agentic CodingClaude Fable 5 by 1.362.260.9+1.3
- Terminal-Bench 2.1tie84.683.9tie
- LMArena · WebDevtie16241622tie
AgentsGLM-5.3
- τ-Bench V3 · BankingGLM-5.3 by 12.238.150.3+12.2
- GDPValGLM-5.3 by 1.955.657.5+1.9
- Terminal-Bench 4.0tie42.441.9tie
ReasoningClaude Fable 5
- SimpleBenchClaude Fable 5 by 15.781.966.2+15.7
- Humanity's Last ExamClaude Fable 5 by 13.255.542.3+13.2
- CritPtClaude Fable 5 by 9.528.619.1+9.5
- LiveBench · ReasoningClaude Fable 5 by 3.989.785.8+3.9
- GPQA Diamondtie92.691.7tie
FactsClaude Fable 5
- AA-Omniscience · Non-hallucinationGLM-5.3 by 3436.470.4+34
- AA-Omniscience · AccuracyClaude Fable 5 by 31.565.333.9+31.5
- SimpleQA VerifiedClaude Fable 5 by 29.770.741+29.7
MathClaude Fable 5
- FrontierMath Tier 4Claude Fable 5 by 60.990.229.3+60.9
- FrontierMath Tiers 1-3 (v2)Claude Fable 5 by 18.28768.8+18.2
- LiveBench · MathematicsClaude Fable 5 by 8.19687.9+8.1
Following instructionsClaude Fable 5
- LiveBench · Instruction FollowingClaude Fable 5 by 6.575.869.3+6.5
Other results17 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 by 67.386.319+67.3
- AA-OmniscienceClaude Fable 5 by 2943.314.3+29
- ToolathlonGLM-5.3 by 11.361.773+11.3
- livebench_languageClaude Fable 5 by 10.890.779.9+10.8
- livebench_data_analysisClaude Fable 5 by 10.380.570.2+10.3
- SWE-MarathonGLM-5.3 by 7.53542.5+7.5
- Toolathlon VerifiedClaude Fable 5 by 4.977.973+4.9
- AA IntelligenceClaude Fable 5 by 4.849.644.8+4.8
- GDPval-AA v2GLM-5.3 by 46 rating points17231769+46 rating
- DeepSWEClaude Fable 5 by 3.17066.9+3.1
- DeepSWE 1.1Claude Fable 5 by 3.17066.9+3.1
- Agents' Last ExamGLM-5.3 by 2.825.728.5+2.8
- Terminal-Bench 4.0Claude Fable 5 by 2.744.541.8+2.7
- AA Agentic IndexGLM-5.3 by 2.45153.4+2.4
- Artificial Analysis Coding IndexClaude Fable 5 by 1.776.574.8+1.7
- PostTrainBenchClaude Fable 5 by 1.641.439.8+1.6
- HLE (with tools)Claude Fable 5 by 1.363.862.5+1.3
Questions people ask
Which is better, Claude Fable 5 or GLM-5.3?
Claude Fable 5 wins six of the seven areas where both have results: coding, reasoning, facts, math, long documents and following instructions. GLM-5.3 wins agents, and costs 90% less.
Which is better for coding?
Claude Fable 5. It wins 3 of the 5 coding tests both models report; GLM-5.3 wins none, and 2 are ties.
Which is cheaper?
Claude Fable 5 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 38 benchmark tests both models have published scores on. The verdict counts the 21 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 17 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.