Claude Opus 4.6 vs GLM-5.3-Flash
Wins 4 of 8 areas
Agents · Facts · Math · Following instructions
Wins 2 of 8 areas
Coding · Long documents
Claude Opus 4.6 wins more areas, narrowly.GLM-5.3-Flash is cheaper and better at coding.
Scores updated · 37 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.
- MathCompetition and research-level math30Claude Opus 4.63 of 3 tests
- AgentsCarrying out multi-step tasks on its own21Claude Opus 4.62 of 3 tests
- FactsGetting facts right instead of making them up21Claude Opus 4.62 of 3 tests
- Following instructionsDoing exactly what it is asked10Claude Opus 4.61 of 1 test
- CodingWriting and fixing software12GLM-5.3-Flash2 of 5 tests · 2 ties
- Long documentsFinding answers in very long texts01GLM-5.3-Flash1 of 1 test
- ReasoningHard problems that need careful thinking22Even2 each · 1 tie
- Images and chartsUnderstanding pictures, charts and video11Even1 each
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-Flash costs 98% 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 Opus 4.6 pulls ahead
- Completes tasks by operating a computer desktopOSWorld-Verified+57.9points ahead
- Answers hard knowledge questions correctlyAA-Omniscience · Accuracy+19.5points ahead
- Short factual questions, answered correctlySimpleQA Verified+15points ahead
Where GLM-5.3-Flash pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+35.2points ahead
- Reasoning about charts from research papersCharXiv (RQ)+12points ahead
- Fixes real GitHub issues, working as an agentLiveBench · Agentic Coding+7.8points ahead
Every test, side by side
All 37 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingGLM-5.3-Flash
- LiveCodeBench v6Claude Opus 4.6 by 8.288.880.6+8.2
- LiveBench · Agentic CodingGLM-5.3-Flash by 7.84956.8+7.8
- LMArena · WebDevGLM-5.3-Flash by 62 rating points15471609+62 rating
- LiveBench · Codingtie78.279tie
- SciCodetie51.951.6tie
AgentsClaude Opus 4.6
- OSWorld-VerifiedClaude Opus 4.6 by 57.972.714.8+57.9
- BrowseCompClaude Opus 4.6 by 88476+8
- GDPValGLM-5.3-Flash by 1.355.957.2+1.3
ReasoningEven
- LiveBench · ReasoningClaude Opus 4.6 by 11.188.777.6+11.1
- ARC-AGI-2Claude Opus 4.6 by 368.865.8+3
- CritPtGLM-5.3-Flash by 2.812.615.4+2.8
- GPQA DiamondGLM-5.3-Flash by 1.689.691.2+1.6
- Humanity's Last Examtie39.939.9tie
FactsClaude Opus 4.6
- AA-Omniscience · Non-hallucinationGLM-5.3-Flash by 35.237.272.4+35.2
- AA-Omniscience · AccuracyClaude Opus 4.6 by 19.54727.5+19.5
- SimpleQA VerifiedClaude Opus 4.6 by 154732+15
Images and chartsEven
- CharXiv (RQ)GLM-5.3-Flash by 1277.489.4+12
- LMArena · VisionClaude Opus 4.6 by 21 rating points13161295+21 rating
MathClaude Opus 4.6
- FrontierMath Tiers 1-3 (v2)Claude Opus 4.6 by 10.26655.8+10.2
- FrontierMath Tier 4Claude Opus 4.6 by 9.726.817.1+9.7
- LiveBench · MathematicsClaude Opus 4.6 by 8.189.381.2+8.1
Following instructionsClaude Opus 4.6
- LiveBench · Instruction FollowingClaude Opus 4.6 by 10.563.352.8+10.5
Other results14 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.
- BabyVisionGLM-5.3-Flash by 38.614.853.4+38.6
- JobBenchGLM-5.3-Flash by 24.136.660.7+24.1
- Artificial Analysis Coding IndexGLM-5.3-Flash by 23.448.171.5+23.4
- ToolathlonGLM-5.3-Flash by 21.656.878.4+21.6
- AA Agentic IndexClaude Opus 4.6 by 16.467.651.2+16.4
- AA IntelligenceGLM-5.3-Flash by 9.931.941.8+9.9
- DeepSearchQA (F1)Claude Opus 4.6 by 791.384.3+7
- livebench_data_analysisGLM-5.3-Flash by 6.569.976.4+6.5
- NL2RepoGLM-5.3-Flash by 6.549.856.3+6.5
- AA-OmniscienceClaude Opus 4.6 by 6.213.77.5+6.2
- livebench_languageClaude Opus 4.6 by 683.377.3+6
- OfficeQA ProGLM-5.3-Flash by 5.357.162.4+5.3
- ARC-AGI-1Claude Opus 4.6 by 29391+2
- Agents' Last ExamGLM-5.3-Flash by 1.125.226.3+1.1
Questions people ask
Which is better, Claude Opus 4.6 or GLM-5.3-Flash?
Claude Opus 4.6 wins four of the eight areas we test: agents, facts, math and following instructions. GLM-5.3-Flash wins coding and long documents, and costs 98% less. They are level on reasoning and images and charts.
Which is better for coding?
GLM-5.3-Flash. It wins 2 of the 5 coding tests both models report; Claude Opus 4.6 wins 1, and 2 are ties.
Which is cheaper?
Claude Opus 4.6 costs $5.00 per million input tokens and $25.00 per million output tokens; GLM-5.3-Flash costs $0.15 and $0.50. That makes GLM-5.3-Flash about 98% cheaper for the same work.
How do you compare the two?
We use the 37 benchmark tests both models have published scores on. The verdict counts the 23 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 14 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.