Claude Sonnet 4 vs GLM-4.5
Wins 3 of 6 areas
Coding · Long documents · Following instructions
Wins 1 of 6 areas
Reasoning
Claude Sonnet 4 wins more areas, narrowly.GLM-4.5 is cheaper and better at reasoning.
Scores updated · 25 tests both models report · How we compare
Where each one wins
Tests won in each of the six 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 software30Claude Sonnet 43 of 3 tests
- Long documentsFinding answers in very long texts10Claude Sonnet 41 of 1 test
- Following instructionsDoing exactly what it is asked10Claude Sonnet 41 of 1 test
- ReasoningHard problems that need careful thinking01GLM-4.51 of 3 tests · 2 ties
- AgentsCarrying out multi-step tasks on its own11Even1 each
- FactsGetting facts right instead of making them up11Even1 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-4.5 costs 84% 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 Sonnet 4 pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+41points ahead
- Reasons across sets of long documentsAA-LCR+17.6points ahead
- Follows unfamiliar, precisely checkable instructionsIFBench+10.6points ahead
Where GLM-4.5 pulls ahead
- Finds hard-to-locate facts by browsing the webBrowseComp+14.2points ahead
- Answers hard knowledge questions correctlyAA-Omniscience · Accuracy+2.4points ahead
- Very hard expert questions across many subjectsHumanity's Last Exam+2.3points ahead
Every test, side by side
All 25 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingClaude Sonnet 4
- Terminal-Bench HardClaude Sonnet 4 by 9.131.122+9.1
- SWE-bench VerifiedClaude Sonnet 4 by 8.572.764.2+8.5
- SciCodeClaude Sonnet 4 by 5.24034.8+5.2
AgentsEven
- BrowseCompGLM-4.5 by 14.212.226.4+14.2
- GDPValClaude Sonnet 4 by 9.79.70+9.7
ReasoningGLM-4.5
- Humanity's Last ExamGLM-4.5 by 2.310.713+2.3
- GPQA Diamondtie77.778.2tie
- CritPttie0.30tie
FactsEven
- AA-Omniscience · Non-hallucinationClaude Sonnet 4 by 4170.929.9+41
- AA-Omniscience · AccuracyGLM-4.5 by 2.422.725.1+2.4
Following instructionsClaude Sonnet 4
- IFBenchClaude Sonnet 4 by 10.654.744.1+10.6
Other results13 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.
- AA-OmniscienceClaude Sonnet 4 by 27.60.2-27.4+27.6
- AIME 2025GLM-4.5 by 22.870.593.3+22.8
- τ²-Bench Telecom (AA run)Claude Sonnet 4 by 21.664.643+21.6
- Artificial Analysis Coding IndexClaude Sonnet 4 by 11.337.626.3+11.3
- AA IntelligenceClaude Sonnet 4 by 6.118.912.8+6.1
- LiveCodeBenchGLM-4.5 by 4.468.572.9+4.4
- MATH-500 (EM)GLM-4.5 by 4.29498.2+4.2
- SWE-Dev (Tools-allowed)Claude Sonnet 4 by 3.967.163.2+3.9
- Terminal-BenchGLM-4.5 by 235.537.5+2
- AA Agentic IndexClaude Sonnet 4 by 1.417.616.2+1.4
- MMLU-Protie83.784.6tie
- TAU-bench (retail)tie80.579.7tie
- TAU-bench (airline)tie6060.4tie
Questions people ask
Which is better, Claude Sonnet 4 or GLM-4.5?
Claude Sonnet 4 wins three of the six areas where both have results: coding, long documents and following instructions. GLM-4.5 wins reasoning, and costs 84% less. They are level on agents and facts.
Which is better for coding?
Claude Sonnet 4. It wins 3 of the 3 coding tests both models report; GLM-4.5 wins none.
Which is cheaper?
Claude Sonnet 4 costs $3.00 per million input tokens and $15.00 per million output tokens; GLM-4.5 costs $0.60 and $2.20. That makes GLM-4.5 about 84% cheaper for the same work.
How do you compare the two?
We use the 25 benchmark tests both models have published scores on. The verdict counts the 12 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 13 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.