AI Model Release Tracker - Timeline of Major AI Models from 2022-2026

Kimi K3 vs GPT-5.5-Pro

Moonshot AI
Kimi K3
OpenAI
GPT-5.5-Pro
Overview
CompanyMoonshot AIOpenAI
Release dateJul 16 2026Apr 23 2026
AccessOpen WeightProprietary
Specifications
Parameters
2.8T
Context window
1M
Benchmarks
Nonsense detection
BullshitBench v2
36%
Agentic coding
DeepSWE 1.0
67.5%
Next.js coding
Next.js Evals
83%
Agentic terminal coding
Terminal-Bench 2.1
88.3%
Multi-step tool use
MCP Atlas
84.2%
Professional tool use
JobBench
52.9%
Personal tool use
Toolathlon-Verified
73.2%
Web browsing
BrowseComp
91.2%Best
90.1%
Multidisciplinary reasoning
Humanity's Last Exam · no tools
43.5%
Multidisciplinary reasoning
Humanity's Last Exam · with tools
56%
57.2%Best
Advanced math
FrontierMath · Tier 1–3
52.4%
Advanced math
FrontierMath · Tier 4
39.6%
Science
GPQA Diamond
93.5%
Knowledge work
GDPval-AA v2
1668
Knowledge work
GDPval (win/tie rate)
82.3%
Chart reasoning
CharXiv Reasoning
84.8%
Multimodal reasoning
MMMU-Pro
81.6%
Timeline
Release gapGPT-5.5-Pro shipped 84 days before Kimi K3

Which is better: Kimi K3 or GPT-5.5-Pro?

Kimi K3 and GPT-5.5-Pro are evenly matched across the 2 benchmarks they both report (BrowseComp, Humanity's Last Exam). GPT-5.5-Pro shipped 84 days before Kimi K3, so benchmark comparisons should account for the intervening progress.

Kimi K3 is open weight, while GPT-5.5-Pro is proprietary.

On BrowseComp, Kimi K3 leads at 91.2% vs GPT-5.5-Pro at 90.1%. On Humanity's Last Exam · with tools, GPT-5.5-Pro leads at 57.2% vs Kimi K3 at 56%.

Frequently asked questions

Kimi K3 was released by Moonshot AI on Jul 16 2026.

GPT-5.5-Pro was released by OpenAI on Apr 23 2026.

GPT-5.5-Pro leads on Humanity's Last Exam · with tools — Kimi K3 56% vs GPT-5.5-Pro 57.2%.

Kimi K3 is an open weight model released by Moonshot AI. GPT-5.5-Pro is a proprietary model released by OpenAI.

Other comparisons