GLM-5.3-Flash vs Claude Opus 5
Wins 0 of 8 areas
—
Wins 6 of 8 areas
Coding · Agents · Reasoning · Facts · Math · Following instructions
Claude Opus 5 is the stronger all-rounder.GLM-5.3-Flash is cheaper.
Scores updated · 40 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 software05Claude Opus 55 of 5 tests
- ReasoningHard problems that need careful thinking05Claude Opus 55 of 5 tests
- AgentsCarrying out multi-step tasks on its own14Claude Opus 54 of 5 tests
- MathCompetition and research-level math03Claude Opus 53 of 3 tests
- FactsGetting facts right instead of making them up12Claude Opus 52 of 3 tests
- Following instructionsDoing exactly what it is asked01Claude Opus 51 of 1 test
- Images and chartsUnderstanding pictures, charts and video11Even1 each
- Long documentsFinding answers in very long texts00Even0 each · 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-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 5 pulls ahead
- Completes tasks by operating a computer desktopOSWorld-Verified+68.6points ahead
- Extremely hard research-level math problemsFrontierMath Tier 4+56.1points ahead
- Answers hard knowledge questions correctlyAA-Omniscience · Accuracy+33.4points ahead
Where GLM-5.3-Flash pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+33.2points ahead
- Reasoning about charts from research papersCharXiv (RQ)+5.7points ahead
- Customer-service tasks in a simulated bankτ-Bench V3 · Banking+5.1points ahead
Every test, side by side
All 40 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingClaude Opus 5
- LiveBench · Agentic CodingClaude Opus 5 by 8.456.865.2+8.4
- LMArena · WebDevClaude Opus 5 by 82 rating points16091691+82 rating
- SciCodeClaude Opus 5 by 4.851.656.4+4.8
- Terminal-Bench 2.1Claude Opus 5 by 4.884.389.1+4.8
- LiveBench · CodingClaude Opus 5 by 2.57981.5+2.5
AgentsClaude Opus 5
- OSWorld-VerifiedClaude Opus 5 by 68.614.883.4+68.6
- Terminal-Bench 4.0Claude Opus 5 by 16.232.849+16.2
- BrowseCompClaude Opus 5 by 14.87690.8+14.8
- τ-Bench V3 · BankingGLM-5.3-Flash by 5.147.242.1+5.1
- GDPValClaude Opus 5 by 3.957.261.1+3.9
ReasoningClaude Opus 5
- ARC-AGI-2Claude Opus 5 by 24.665.890.4+24.6
- Humanity's Last ExamClaude Opus 5 by 1539.954.9+15
- CritPtClaude Opus 5 by 13.715.429.1+13.7
- LiveBench · ReasoningClaude Opus 5 by 13.677.691.2+13.6
- GPQA DiamondClaude Opus 5 by 291.293.2+2
FactsClaude Opus 5
- AA-Omniscience · AccuracyClaude Opus 5 by 33.427.560.9+33.4
- AA-Omniscience · Non-hallucinationGLM-5.3-Flash by 33.272.439.2+33.2
- SimpleQA VerifiedClaude Opus 5 by 27.93259.9+27.9
Images and chartsEven
- CharXiv (RQ)GLM-5.3-Flash by 5.789.483.7+5.7
- LMArena · VisionClaude Opus 5 by 22 rating points12951317+22 rating
MathClaude Opus 5
- FrontierMath Tier 4Claude Opus 5 by 56.117.173.2+56.1
- FrontierMath Tiers 1-3 (v2)Claude Opus 5 by 29.855.885.6+29.8
- LiveBench · MathematicsClaude Opus 5 by 14.581.295.7+14.5
Following instructionsClaude Opus 5
- LiveBench · Instruction FollowingClaude Opus 5 by 1152.863.8+11
Other results15 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.
- GDP (Surge AI)Claude Opus 5 by 70.115.485.5+70.1
- BabyVisionClaude Opus 5 by 40.753.494.1+40.7
- AA-OmniscienceClaude Opus 5 by 29.67.537.1+29.6
- Terminal-Bench-Science 0.1Claude Opus 5 by 24.24.829+24.2
- livebench_languageClaude Opus 5 by 11.477.388.7+11.4
- AA IntelligenceClaude Opus 5 by 941.850.8+9
- ARC-AGI-1Claude Opus 5 by 6.59197.5+6.5
- Artificial Analysis Coding IndexClaude Opus 5 by 6.571.578+6.5
- GDPval-AA 2.1Claude Opus 5 by 59 rating points16491708+59 rating
- DeepSWE 1.1Claude Opus 5 by 5.463.468.8+5.4
- AA Agentic IndexClaude Opus 5 by 551.256.2+5
- JobBenchClaude Opus 5 by 560.765.7+5
- OfficeQA ProClaude Opus 5 by 4.562.466.9+4.5
- Agents' Last ExamClaude Opus 5 by 2.326.328.6+2.3
- livebench_data_analysisGLM-5.3-Flash by 1.876.474.5+1.8
Questions people ask
Which is better, GLM-5.3-Flash or Claude Opus 5?
Claude Opus 5 wins six of the eight areas we test: coding, agents, reasoning, facts, math and following instructions. GLM-5.3-Flash wins none, but costs 98% less. They are level on images and charts and long documents.
Which is better for coding?
Claude Opus 5. It wins 5 of the 5 coding tests both models report; GLM-5.3-Flash wins none.
Which is cheaper?
GLM-5.3-Flash costs $0.15 per million input tokens and $0.50 per million output tokens; Claude Opus 5 costs $5.00 and $25.00. That makes GLM-5.3-Flash about 98% cheaper for the same work.
How do you compare the two?
We use the 40 benchmark tests both models have published scores on. The verdict counts the 25 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 15 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.