Claude Opus 4.8 vs GPT-5.1
Wins 5 of 7 areas
Coding · Agents · Reasoning · Facts · Images and charts
Wins 2 of 7 areas
Long documents · Following instructions
Claude Opus 4.8 is the stronger all-rounder.GPT-5.1 is cheaper and better at long documents.
Scores updated · 30 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.
- CodingWriting and fixing software50Claude Opus 4.85 of 5 tests
- ReasoningHard problems that need careful thinking50Claude Opus 4.85 of 5 tests
- AgentsCarrying out multi-step tasks on its own30Claude Opus 4.83 of 3 tests
- FactsGetting facts right instead of making them up30Claude Opus 4.83 of 3 tests
- Images and chartsUnderstanding pictures, charts and video10Claude Opus 4.81 of 1 test
- Long documentsFinding answers in very long texts01GPT-5.11 of 1 test
- Following instructionsDoing exactly what it is asked01GPT-5.11 of 1 test
Images and charts, 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.
GPT-5.1 costs 63% less for the same work.
The biggest differences
The tests each model wins by the widest margin, up to three each. Scores are out of 100.
Where Claude Opus 4.8 pulls ahead
- Abstract visual puzzles that people can solveARC-AGI-2+54.5points ahead
- Finds hard-to-locate facts by browsing the webBrowseComp+33.5points ahead
- Command-line tasks in a real terminalTerminal-Bench 2.1+32.2points ahead
Every test, side by side
All 30 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingClaude Opus 4.8
- Terminal-Bench 2.1Claude Opus 4.8 by 32.284.652.4+32.2
- LMArena · WebDevClaude Opus 4.8 by 161 rating points15561395+161 rating
- Terminal-Bench HardClaude Opus 4.8 by 12.858.345.5+12.8
- SWE-bench VerifiedClaude Opus 4.8 by 12.388.676.3+12.3
- SciCodeClaude Opus 4.8 by 11.154.443.3+11.1
AgentsClaude Opus 4.8
- BrowseCompClaude Opus 4.8 by 33.584.350.8+33.5
- GDPValClaude Opus 4.8 by 31.347.816.5+31.3
- τ-Bench V3 · BankingClaude Opus 4.8 by 18.334.215.9+18.3
ReasoningClaude Opus 4.8
- ARC-AGI-2Claude Opus 4.8 by 54.572.117.6+54.5
- Humanity's Last ExamClaude Opus 4.8 by 20.248.728.5+20.2
- CritPtClaude Opus 4.8 by 1620.94.9+16
- SimpleBenchClaude Opus 4.8 by 11.664.853.2+11.6
- GPQA DiamondClaude Opus 4.8 by 4.79287.3+4.7
FactsClaude Opus 4.8
- AA-Omniscience · Non-hallucinationClaude Opus 4.8 by 12.660.748.1+12.6
- AA-Omniscience · AccuracyClaude Opus 4.8 by 11.148.837.7+11.1
- SimpleQA VerifiedClaude Opus 4.8 by 55348+5
Images and chartsClaude Opus 4.8
- LMArena · VisionClaude Opus 4.8 by 45 rating points12951250+45 rating
Other results11 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.
- Terminal-Bench 2.0Claude Opus 4.8 by 2774.647.6+27
- Artificial Analysis Coding IndexClaude Opus 4.8 by 24.974.349.4+24.9
- AA-OmniscienceClaude Opus 4.8 by 23.428.85.4+23.4
- AA Agentic IndexClaude Opus 4.8 by 2142.621.6+21
- ARC-AGI-1Claude Opus 4.8 by 19.792.572.8+19.7
- frontiermath_tier_4_v1Claude Opus 4.8 by 18.831.312.5+18.8
- AA IntelligenceClaude Opus 4.8 by 17.141.824.7+17.1
- HLE (with tools)Claude Opus 4.8 by 15.257.942.7+15.2
- τ²-Bench Telecom (AA run)Claude Opus 4.8 by 12.594.481.9+12.5
- HMMT Nov. 2025Claude Opus 4.8 by 4.896.591.7+4.8
- matharena_visual_math_overallClaude Opus 4.8 by 4.781.676.9+4.7
Questions people ask
Which is better, Claude Opus 4.8 or GPT-5.1?
Claude Opus 4.8 wins five of the seven areas where both have results: coding, agents, reasoning, facts and images and charts. GPT-5.1 wins long documents and following instructions, and costs 63% less.
Which is better for coding?
Claude Opus 4.8. It wins 5 of the 5 coding tests both models report; GPT-5.1 wins none.
Which is cheaper?
Claude Opus 4.8 costs $5.00 per million input tokens and $25.00 per million output tokens; GPT-5.1 costs $1.25 and $10.00. That makes GPT-5.1 about 63% cheaper for the same work.
How do you compare the two?
We use the 30 benchmark tests both models have published scores on. The verdict counts the 19 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 11 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.