Compare

GPT-5.5 Pro vs Kimi-K2.6

Pricing per million tokens, context window, capabilities — pulled from each provider's public docs. All 2 are available via the same AIgateway OpenAI-compatible endpoint; flip the model string to switch.

Search2/4
GPT-5.5 Pro
openai/gpt-5.5-pro
Kimi-K2.6
moonshot/kimi-k2.6
Provider
OpenAI
Moonshot
Family
GPT-5
Kimi
Modality
text
text
Context window
1,000,000 tok
262,144 tok
Max output
16,384 tok
16,384 tok
Released
2026-05-22
2026-04-20
License
Proprietary
Open-weight
Input price
$30.00 /1M
$0.950 /1M
Output price
$180.00 /1M
$4.00 /1M
Cache read
—
$0.160 /1M
Tools
yes
yes
Streaming
yes
yes
Vision
yes
yes
JSON mode
yes
yes
Reasoning
yes
yes
Prompt caching
—
yes
Batch API
—
—
Try it
Open in playground →
Open in playground →
GPT-5.5 Pro
openai/gpt-5.5-pro
Full spec →

GPT-5.5 pro uses OpenAI's Responses API with built-in tools, improved reasoning, and stateful context management.

Strengths
  • General-purpose chat
  • Long context
  • Tool use
Use cases
ChatbotsContent generationAgentic workflows
Kimi-K2.6
moonshot/kimi-k2.6
Full spec →

Kimi K2.6 is a frontier-scale open-source 1T parameter model with a 262.1k context window, multi-turn tool calling, vision inputs, and structured outputs for agentic workloads.

Strengths
  • Frontier-scale 1T parameters, open-weight
  • ~10× cheaper than Opus
  • Multi-turn tool calling + vision
Use cases
Code agentsLong-document reasoningCost-conscious production

Benchmarks

GPT-5.5 Pro
Kimi-K2.6
HumanEval
—
92.7
SWE-Bench
—
68.2

Source: each provider's published benchmarks. Higher is better. Run an eval to compare on your own data.

Compare with another

Kimi-K2.6 vs Kimi-K2.7-Code
moonshot/kimi-k2.6 · moonshot/kimi-k2.7-code
Gemini 4 Argon vs GPT-5.5 Pro
google/gemini-4-argon · openai/gpt-5.5-pro
Claude Sonnet 5.5 vs GPT-5.5 Pro
anthropic/claude-sonnet-5.5 · openai/gpt-5.5-pro
Claude Opus 5.5 vs GPT-5.5 Pro
anthropic/claude-opus-5.5 · openai/gpt-5.5-pro
GPT-6.1 Sol vs GPT-5.5 Pro
openai/gpt-6.1-sol · openai/gpt-5.5-pro
Grok 4.7 vs GPT-5.5 Pro
xai/grok-4.7 · openai/gpt-5.5-pro
Kimi K3 vs GPT-5.5 Pro
moonshot/kimi-k3 · openai/gpt-5.5-pro
Glm-5.3 vs GPT-5.5 Pro
zai-org/glm-5.3 · openai/gpt-5.5-pro
Qwen3.8-Max vs GPT-5.5 Pro
alibaba/qwen3.8-max · openai/gpt-5.5-pro
SWITCH BETWEEN THEM

One key, all 2, one line different.

from openai import OpenAI

client = OpenAI(
    base_url="https://api.aigateway.sh/v1",
    api_key="sk-aig-...",
)

# GPT-5.5 Pro
client.chat.completions.create(
    model="openai/gpt-5.5-pro",
    messages=[{"role":"user","content":"hello"}],
)

# Kimi-K2.6
client.chat.completions.create(
    model="moonshot/kimi-k2.6",
    messages=[{"role":"user","content":"hello"}],
)
Get an AIgateway keyRun an eval on these →