Kimi K3.1 Pro is the stronger all-rounder.
Scores updated · 17 tests both models report · How we compare
Where each one wins
Tests won in each of the four 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.
Coding and images and charts 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.
Kimi K3.1 Pro costs 60% 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 Kimi K3.1 Pro pulls ahead
- Long professional tasks in banking, consulting and lawAA ApexAgents+27.8points ahead
- Finds hard-to-locate facts by browsing the webBrowseComp+7.8points ahead
- Very hard expert questions across many subjectsHumanity's Last Exam+2.4points ahead
Where Claude Opus 4.8 pulls ahead
No clear win on a test scored out of 100.
Every test, side by side
All 17 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingKimi K3.1 Pro
- LMArena · WebDevKimi K3.1 Pro by 139 rating points15561695+139 rating
AgentsKimi K3.1 Pro
- AA ApexAgentsKimi K3.1 Pro by 27.839.467.2+27.8
- BrowseCompKimi K3.1 Pro by 7.884.392.1+7.8
ReasoningKimi K3.1 Pro
- Humanity's Last ExamKimi K3.1 Pro by 2.448.751.1+2.4
- GPQA DiamondKimi K3.1 Pro by 2.29294.2+2.2
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.
- GDP (Surge AI)Claude Opus 4.8 by 50.284.834.6+50.2
- Terminal-Bench 4.0Kimi K3.1 Pro by 42.123.665.7+42.1
- Program BenchClaude Opus 4.8 by 40.471.931.5+40.4
- SWE-MarathonKimi K3.1 Pro by 25.72651.7+25.7
- Agents' Last ExamKimi K3.1 Pro by 17.525.743.2+17.5
- DeepSWEKimi K3.1 Pro by 17.55875.5+17.5
- DeepSWE 1.1Kimi K3.1 Pro by 16.55975.5+16.5
- HLE (with tools)Kimi K3.1 Pro by 12.157.970+12.1
- AA IntelligenceKimi K3.1 Pro by 4.241.846+4.2
- OfficeQA ProKimi K3.1 Pro by 1.266.267.4+1.2
- PostTrainBenchtie37.236.5tie
Questions people ask
Which is better, Claude Opus 4.8 or Kimi K3.1 Pro?
Kimi K3.1 Pro wins three of the four areas where both have results: coding, agents and reasoning. Claude Opus 4.8 wins none. They are level on images and charts.
Which is better for coding?
Kimi K3.1 Pro. It wins the one coding test both models report.
Which is cheaper?
Claude Opus 4.8 costs $5.00 per million input tokens and $25.00 per million output tokens; Kimi K3.1 Pro costs $2.00 and $10.00. That makes Kimi K3.1 Pro about 60% cheaper for the same work.
How do you compare the two?
We use the 17 benchmark tests both models have published scores on. The verdict counts the 6 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.