Compare / head-to-head

Claude Opus 4.8vsKimi K2.5

Claude Opus 4.8 leads 12 of 12 shared benchmarks. Claude Opus 4.8 has the larger context window (1M tokens).

Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.

Shared benchmarks
12 – 0
Claude Opus 4.8 leads
Cheaper per token
—
list price, input + output
Larger context
Claude Opus 4.8
1M tokens
Providers
2 providers
Anthropic · Moonshot AI
Claude Opus 4.8
Anthropic · released 2026-05-28
textvision
Context
1M
Max out
128K
Input /1M
$5 ↗
Output /1M
$25 ↗
Cached /1M
$0.5
Scores
47 · 16 core
Kimi K2.5
Moonshot AI · released 2026-01-27
textvisionvideo
Context
256K
Max out
—
Input /1M
—
Output /1M
—
Cached /1M
—
Scores
26 · 14 core
Quality

Benchmark matrix

BenchmarkClaude Opus 4.8Kimi K2.5ΔEdge
Reported by both · 12
SWE-bench Verified88.6% ↗76.8% ↗+11.8 ptClaude Opus 4.8
LMArena Elo1452.7 ↗1450.1 ↗+2.6Claude Opus 4.8
BrowseComp84.3% ↗60.6% ↗+23.7 ptClaude Opus 4.8
LMArena Vision (LMArena)1286.4 ↗1252.2 ↗+34.2Claude Opus 4.8
LMArena WebDev (LMArena)1555.5 ↗1435.8 ↗+119.7Claude Opus 4.8
SAGE (Vals AI)54.8% ↗49.9% ↗+4.9 ptClaude Opus 4.8
SimpleBench (SimpleBench)64.8% ↗46.8% ↗+18 ptClaude Opus 4.8
SimpleQA Verified53% ↗epoch run34.3% ↗epoch run+18.7 ptClaude Opus 4.8
SWE-Bench Pro69.2% ↗50.7% ↗+18.5 ptClaude Opus 4.8
Toolathlon-Verified (HKUST)76.2% ↗33% ↗+43.2 ptClaude Opus 4.8
Vending-Bench 2 (Andon Labs)5787.43 ↗1198.46 ↗+4589Claude Opus 4.8
WeirdML (Håvard Tveit Ihle)82.9% ↗45.6% ↗+37.3 ptClaude Opus 4.8
Only Claude Opus 4.8 reports · 28
GPQA Diamond93.6% ↗not reported——
AIME 2026100% ↗matharena ⚠not reported——
Humanity's Last Exam (no tools)49.8% ↗not reported——
APEX-Agents (Mercor)48.9% ↗not reported——
Chess Puzzles (Epoch AI run)34% ↗epoch runnot reported——
DeepSWE v1.1 (Datacurve)59% ↗not reported——
EBR-bench (Epoch AI run)28.6% ↗epoch runnot reported——
FrontierMath Tier 4 v2 (Epoch AI run)56.1% ↗epoch runnot reported——
FrontierMath Tiers 1-3 v2 (Epoch AI run)80% ↗epoch runnot reported——
Furniture Assembly (Epoch AI run)42.5% ↗epoch runnot reported——
GSO Opt@1 (GSO)47.1% ↗not reported——
Humanity's Last Exam (with tools)57.9% ↗not reported——
LiveBench Agentic Coding (LiveBench)50.5% ↗not reported——
LiveBench Coding (LiveBench)81.8% ↗not reported——
LiveBench Data Analysis (LiveBench)66% ↗not reported——
LiveBench Instruction Following (LiveBench)72% ↗not reported——
LiveBench Language (LiveBench)79.7% ↗not reported——
LiveBench Mathematics (LiveBench)94.3% ↗not reported——
LiveBench Reasoning (LiveBench)89.2% ↗not reported——
LMArena Agent (LMArena)0.0664 ↗not reported——
Mystery Game Puzzles (Epoch AI run)36% ↗epoch runnot reported——
OSWorld-Verified83.4% ↗not reported——
OTIS Mock AIME 2024-2025 (Epoch AI run)98.3% ↗epoch runnot reported——
SWE-bench Multilingual84.4% ↗not reported——
SWE-bench Multimodal38.4% ↗not reported——
tau2-bench Banking Knowledge (Sierra)39.7% ↗not reported——
Terminal-Bench 2.174.6% ↗not reported——
Terminal-Bench 4.0 (Vals AI)23.2% ↗not reported——
Only Kimi K2.5 reports · 14
MMLU-Pronot reported87.1% ↗——
AIME 2025not reported96.1% ↗——
GPQA-Diamondnot reported87.6% ↗——
HLE-Fullnot reported30.1% ↗——
HLE-Full (w/ tools)not reported50.2% ↗——
HMMT 2025 (Feb)not reported95.4% ↗——
IMO-AnswerBenchnot reported81.8% ↗——
LiveCodeBench (v6)not reported85% ↗——
MMMU-Pronot reported78.5% ↗——
OSWorld-Verified (XLANG)not reported63.3% ↗——
SWE-Bench Multilingualnot reported73% ↗——
SWE-bench Verified (Epoch AI run)not reported73.8% ↗epoch run——
Terminal Bench 2.0not reported50.8% ↗——
VideoMMMUnot reported86.6% ↗——
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is Claude Opus 4.8 minus Kimi K2.5 in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing

Side by side

SpecClaude Opus 4.8Kimi K2.5Edge
Context window1M tokens256K tokensClaude Opus 4.8
Max output128K tokens——
Input price / 1M$5 ↗——
Output price / 1M$25 ↗——
Cached input / 1M$0.5 ↗——
Input + output / 1M
Lower is cheaper. List prices; batch, tool and regional fees excluded.
$30——
Modalitiestext · visiontext · vision · videoKimi K2.5
Released2026-05-282026-01-27—
Cited benchmark scores4726—
Reliability

Provider status

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