Compare / head-to-head

GPT-5vsKimi K2

GPT-5 leads 4 of 4 shared benchmarks. GPT-5 has the larger context window (400K tokens).

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

Shared benchmarks
4 – 0
GPT-5 leads
Cheaper per token
—
list price, input + output
Larger context
GPT-5
400K tokens
Providers
2 providers
OpenAI · Moonshot AI
GPT-5
OpenAI · released 2025-08-07
textvision
Context
400K
Max out
128K
Input /1M
$1.25 ↗
Output /1M
$10 ↗
Cached /1M
$0.125
Scores
27 · 11 core
Kimi K2
Moonshot AI · released 2025-07-11
text
Context
128K
Max out
—
Input /1M
—
Output /1M
—
Cached /1M
—
Scores
18 · 7 core
Quality

Benchmark matrix

BenchmarkGPT-5Kimi K2ΔEdge
Reported by both · 4
AIME 202594.6% ↗49.5% ↗+45.1 ptGPT-5
GSO Opt@1 (GSO)5.9% ↗2% ↗+3.9 ptGPT-5
SimpleBench (SimpleBench)56.7% ↗26.3% ↗+30.4 ptGPT-5
WeirdML (Håvard Tveit Ihle)60.7% ↗39.4% ↗+21.3 ptGPT-5
Only GPT-5 reports · 16
SWE-bench Verified74.9% ↗not reported——
GPQA Diamond86.2% ↗epoch runnot reported——
LMArena Elo1434.5 ↗not reported——
BALROG (BALROG)32.8% ↗not reported——
Chess Puzzles (Epoch AI run)37% ↗epoch runnot reported——
EBR-bench (Epoch AI run)12.7% ↗epoch runnot reported——
FrontierMath Tier 4 v2 (Epoch AI run)22% ↗epoch runnot reported——
FrontierMath Tiers 1-3 v2 (Epoch AI run)55.4% ↗epoch runnot reported——
LMArena Vision (LMArena)1210.2 ↗not reported——
LMArena WebDev (LMArena)1417.1 ↗not reported——
MATH Level 5 (Epoch AI run)98.1% ↗epoch runnot reported——
Mystery Game Puzzles (Epoch AI run)23% ↗epoch runnot reported——
OTIS Mock AIME 2024-2025 (Epoch AI run)91.4% ↗epoch runnot reported——
SAGE (Vals AI)43.7% ↗not reported——
SimpleQA Verified50.1% ↗epoch runnot reported——
SWE-bench Verified (Epoch AI run)73.6% ↗epoch runnot reported——
Only Kimi K2 reports · 14
MMLU-Pronot reported81.1% ↗——
Aider-Polyglotnot reported60% ↗——
GPQA-Diamondnot reported75.1% ↗——
Humanity's Last Exam (Text Only)not reported4.7% ↗——
IFEval (Prompt Strict)not reported89.8% ↗——
LiveCodeBench v6 (Aug 24 - May 25)not reported53.7% ↗——
MMLU-Reduxnot reported92.7% ↗——
SimpleQAnot reported31% ↗——
SWE-bench Multilingual (Agentic Coding, single attempt)not reported47.3% ↗——
SWE-bench Verified (Agentic Coding, single attempt)not reported65.8% ↗——
Tau2 airlinenot reported56.5% ↗——
Tau2 retailnot reported70.6% ↗——
Tau2 telecomnot reported65.8% ↗——
TerminalBench (Inhouse Framework)not reported30% ↗——
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 GPT-5 minus Kimi K2 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

SpecGPT-5Kimi K2Edge
Context window400K tokens128K tokensGPT-5
Max output128K tokens——
Input price / 1M$1.25 ↗——
Output price / 1M$10 ↗——
Cached input / 1M$0.125 ↗——
Input + output / 1M
Lower is cheaper. List prices; batch, tool and regional fees excluded.
$11.25——
Modalitiestext · visiontextGPT-5
Released2025-08-072025-07-11—
Cited benchmark scores2718—
Reliability

Provider status

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