Model comparison

Claude Fable 5.1 vs GLM-5.3

Claude Fable 5.1 is the stronger model overall, scoring 69.0 to 54.8 on the Noometry Index. GLM-5.3 costs 9.3× less per token, which makes it the better buy when Claude Fable 5.1's lead doesn't matter for your workload.

Last verified . 39 shared benchmarks.

Claude Fable 5.1 Anthropic

69.0

Rank #2 Confirmed

GLM-5.3 Z.ai (Zhipu)

54.8

Rank #26 Confirmed

Summary

  • They share 39 benchmarks with published results for both. Claude Fable 5.1 scores higher in 9 categories and GLM-5.3 in 0 categories; 9 gaps are clear of the uncertainty.
  • The widest gap is in reasoning, where Claude Fable 5.1 leads 76.7 to 46.1.
  • The biggest single-benchmark swing is FrontierMath Tier 4: 87.8% for Claude Fable 5.1 and 29.3% for GLM-5.3.
  • GLM-5.3 is cheaper at $1.40 / $4.40 per million input/output tokens, against $10 / $50 for Claude Fable 5.1.
  • GLM-5.3 has downloadable open weights; the other is API-only.

Side by side

Claude Fable 5.1 and GLM-5.3 specifications
Claude Fable 5.1GLM-5.3
ProviderAnthropicZ.ai (Zhipu)
Noometry Index69.054.8
Released2026-09-012026-08-14
WeightsProprietaryOpen
Context window1M1M
Max output128K131K
Input $ / M tokens$10$1.40
Output $ / M tokens$50$4.40
Results tracked5242

Sponsored placements are available on pages like this one. Advertise on Noometry

Category by category

Coding Claude Fable 5.1 leads

Claude Fable 5.1: 74.7 (#1), GLM-5.3: 59.5 (#14)

Coding benchmarks
BenchmarkClaude Fable 5.1GLM-5.3
FrontierCode50.9%40.1%
CursorBench51.8%42.6%
LMArena WebDev17441622
FrontierSWE56.3%30.2%
SciCode63.1%59%
WeirdML92.9%75.4%
LMArena Coding15281496
ALE-Bench2,1431,317
DeepSWE—69%
GSO88.2%—
MirrorCode73.3%—

Agentic & Tool Use Claude Fable 5.1 leads

Claude Fable 5.1: 50.7 (#5), GLM-5.3: 36.4 (#38)

Agentic & Tool Use benchmarks
BenchmarkClaude Fable 5.1GLM-5.3
APEX-Agents68.6%56.6%
Vending-Bench 25,4228,164
Remote Labor Index17.9%—
GDP.pdf29.6%—

Reasoning Claude Fable 5.1 leads

Claude Fable 5.1: 76.7 (#7), GLM-5.3: 46.1 (#46)

Reasoning benchmarks
BenchmarkClaude Fable 5.1GLM-5.3
NYT Connections (extended)90%74.2%
CritPt31.1%19.1%
Chess Puzzles47%21%
LMArena Hard Prompts15261489
Mystery Game Puzzles58%33%
DTBench97.6%87.7%
LMCA65.5%55.5%
Epoch Capabilities Index164.7155.61
ARC-AGI-290%—
ARC-AGI-197.5%—
EBR-Bench57.1%—
Bench to the Future 3—0.15

Math Claude Fable 5.1 leads

Claude Fable 5.1: 89.6 (#4), GLM-5.3: 62.3 (#33)

Math benchmarks
BenchmarkClaude Fable 5.1GLM-5.3
FrontierMath (Tiers 1-3)90.2%68.8%
FrontierMath Tier 487.8%29.3%
OTIS Mock AIME 2024-2025100%91.1%
ProofBench100%49%
LMArena Math15251489
FrontierMath Erdős0%—

Knowledge Claude Fable 5.1 leads

Claude Fable 5.1: 69.6 (#6), GLM-5.3: 58.3 (#37)

Knowledge benchmarks
BenchmarkClaude Fable 5.1GLM-5.3
SimpleQA Verified70.8%41%
LMArena Expert15351516
GPQA Diamond—90.9%
Humanity's Last Exam46.5%—

Multimodal Not comparable

Claude Fable 5.1: 53.9 (#4), GLM-5.3: —

Multimodal benchmarks
BenchmarkClaude Fable 5.1GLM-5.3
LMArena Vision1318—
Blueprint-Bench 241.9%—
Furniture Assembly70%—
LMArena Document1513—

Multilingual Claude Fable 5.1 leads

Claude Fable 5.1: 59.1 (#3), GLM-5.3: 55.7 (#28)

Multilingual benchmarks
BenchmarkClaude Fable 5.1GLM-5.3
LMArena Non-English15071457
LMArena Chinese15861528
LMArena French15251499
LMArena German15001499
LMArena Japanese15431453
LMArena Korean15341472
LMArena Russian15211463
LMArena Spanish15161460

Instruction Following Claude Fable 5.1 leads

Claude Fable 5.1: 79.2 (#6), GLM-5.3: 77.5 (#23)

Instruction Following benchmarks
BenchmarkClaude Fable 5.1GLM-5.3
LMArena Instruction Following15171477

Long Context Claude Fable 5.1 leads

Claude Fable 5.1: 46.7 (#20), GLM-5.3: 45.4 (#41)

Long Context benchmarks
BenchmarkClaude Fable 5.1GLM-5.3
LMArena Longer Query15221482

Writing & Preference Claude Fable 5.1 leads

Claude Fable 5.1: 79.2 (#2), GLM-5.3: 75.7 (#6)

Writing & Preference benchmarks
BenchmarkClaude Fable 5.1GLM-5.3
LMArena Text15101471
LMArena Creative Writing15071457
EQ-Bench Creative Writing21622075
LMArena Multi-Turn14921472

Frequently asked questions

Is Claude Fable 5.1 better than GLM-5.3?

Claude Fable 5.1 is the stronger model overall, scoring 69.0 to 54.8 on the Noometry Index. GLM-5.3 costs 9.3× less per token, which makes it the better buy when Claude Fable 5.1's lead doesn't matter for your workload.

Which is cheaper, Claude Fable 5.1 or GLM-5.3?

GLM-5.3 is cheaper. It lists at $1.40 per million input tokens and $4.40 per million output tokens; Claude Fable 5.1 lists at $10 and $50.

Is Claude Fable 5.1 or GLM-5.3 better for coding?

Claude Fable 5.1 scores higher on coding benchmarks: 74.7 versus 59.5 in the Noometry coding category.

Which has the bigger context window?

Both accept 1M tokens.

How many benchmarks do Claude Fable 5.1 and GLM-5.3 share?

39 benchmarks have published results for both models. Claude Fable 5.1 has 52 scored results on Noometry and GLM-5.3 has 42.

Related comparisons

Go deeper