The Known Good Updated 2 Sep 2026 Subscribe
MoonshotAI: Kimi K2.6 vs OpenAI: GPT-5.5 ·Moonshot AI vs OpenAI

MoonshotAI: Kimi K2.6 vs OpenAI: GPT-5.5 — head-to-head comparison

MoonshotAI: Kimi K2.6 profile OpenAI: GPT-5.5 profile All comparisons
MoonshotAI: Kimi K2.6 — Moonshot AI
Quality
#7 of 65
93based on 3 of 7 evaluations
Known Good Index
Speed
#157 of 339
51.9
Output tokens per second
Price
#288 of 439
$1.71
Blended per 1M tokens
In $0.95 · Out $4.00
Cache hit price
#210 of 322
$0.16
per 1M tokens (−83%)
Context
#264 of 473
262k
tokens (~400 pages)
OpenAI: GPT-5.5 — OpenAI
Quality
#5 of 65
93based on 3 of 7 evaluations
Known Good Index
Speed
#65 of 339
85.0
Output tokens per second
Price
#412 of 439
$11.25
Blended per 1M tokens
In $5.00 · Out $30.00
Cache hit price
#295 of 322
$0.50
per 1M tokens (−90%)
Context
#30 of 473
1.05M
tokens (~1,600 pages)
Summary

On the Known Good Index, MoonshotAI: Kimi K2.6 scores 93 and OpenAI: GPT-5.5 scores 93, which puts them level. They share 2 published evaluations, with MoonshotAI: Kimi K2.6 ahead on 2 and OpenAI: GPT-5.5 ahead on 0.

Blended pricing is $1.71 per 1M tokens for MoonshotAI: Kimi K2.6 and $11.25 for OpenAI: GPT-5.5 — MoonshotAI: Kimi K2.6 is about 6.6× cheaper.

Throughput is 52 tokens per second for MoonshotAI: Kimi K2.6 and 85 for OpenAI: GPT-5.5, with time to first token at 1.4s and 4.9s. MoonshotAI: Kimi K2.6 accepts 262k tokens of context against 1.05M.

MoonshotAI: Kimi K2.6 is open weights under Open weights (unrestricted); OpenAI: GPT-5.5 is proprietary. 26 tracked hosts serve one or both.

Generated from tracked data on 3 Sep 2026 · how these comparisons are computed →

At a glance
MetricMoonshotAI: Kimi K2.6OpenAI: GPT-5.5
Known Good Index 93 based on 3 of 7 evaluations 93 based on 3 of 7 evaluations
Blended $/1M $1.71 $11.25
Output tok/s 52 85
Context window 262k 1.05M
Providers 23 3
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Quality

Known Good Index and the capability indices, side by side

Index scores

Each index is min-max normalised across tracked models and scaled 0–100 from published evaluations. We do not run these evaluations.

MetricMoonshotAI: Kimi K2.6OpenAI: GPT-5.5
Known Good Index 93 93
Openness Index 60 5
The Known Good

Quality Breakdown

Every evaluation both models report a published score for

Evaluations both models report

Bar = MoonshotAI: Kimi K2.6 · marker = OpenAI: GPT-5.5 · scores ingested from Epoch AI (CC-BY 4.0)

GPQA Diamond91 / 91
Mock AIME 2024–2596 / 84

Right-hand figures read MoonshotAI: Kimi K2.6 / OpenAI: GPT-5.5. MoonshotAI: Kimi K2.6 leads on 2 of 2, OpenAI: GPT-5.5 on 0.

The Known Good

Arena Elo

Human preference rating from blind pairwise votes

Arena ratings

Elo from blind pairwise votes, ingested from Arena. Higher is better.

MetricMoonshotAI: Kimi K2.6OpenAI: GPT-5.5
Text Arena 1,455 1,467
Text Arena (style controlled) 1,461 1,477
The Known Good

Price & Cost

Published API pricing by token type

Published pricing

USD per 1M tokens. Blended is a 3:1 input:output mix. Live from OpenRouter, cross-checked against models.dev. Lower is better.

MetricMoonshotAI: Kimi K2.6OpenAI: GPT-5.5
Input $/1M $0.95 $5.00
Output $/1M $4.00 $30.00
Blended $/1M $1.71 $11.25
Cache read $/1M $0.160 $0.500
The Known Good
We publish blended price rather than cost-per-task. Cost-per-task requires token counts from an evaluation suite we do not run. Blended price is computed from published rates and is fully reproducible — see the pricing methodology.

Context Window

Maximum input accepted and maximum output emitted

Context and output limits

Provider-declared limits, from metadata via models.dev and OpenRouter. Higher is better.

MetricMoonshotAI: Kimi K2.6OpenAI: GPT-5.5
Context window 262k 1.05M
Max output tokens 236k 128k
The Known Good

Speed & Latency

Mean throughput and time to first token across hosting providers, over successful measurements from the last 48 hours

Throughput and latency

Means across all tracked providers over successful measurements from the last 48 hours, derived from OpenRouter endpoint telemetry.

MetricMoonshotAI: Kimi K2.6OpenAI: GPT-5.5
Output tokens/s 52 85
Time to first token 1.4s 4.9s
The Known Good

Providers

Which hosts serve each model, and at what price and speed

26 hosts
Full provider benchmarks →
Provider MoonshotAI: Kimi K2.6 blendedMoonshotAI: Kimi K2.6 tok/s OpenAI: GPT-5.5 blendedOpenAI: GPT-5.5 tok/s
CoreWeave $1.34 255
BaseTen $1.71 193
Together $2.02 119
ModelRun $1.38 103
Decart $1.00 85
Parasail $1.44 73
Cloudflare $1.71 58
Baidu · first party $1.71 54
Inceptron $1.02 46
SiliconFlow $1.43 43
Fireworks $1.71 42
Chutes $1.28 41
DigitalOcean $1.71 39
Novita $1.45 38
StreamLake $1.08 34
Sail Research $1.75 33
AtlasCloud $1.71 31
Phala $1.97 31
Moonshot AI · first party $1.71 28
Venice $1.44 24
Crusoe $1.40 22
DeepInfra $1.44 20
GMICloud $1.54 8
Amazon Bedrock · first party $12.38 180
OpenAI · first party $5.62 70
Azure · first party $11.25 54

Per-host pricing and telemetry from OpenRouter. A dash means that host does not serve that model.

The Known Good
Sources for this page
Pricing & providers — OpenRouter Metadata — models.dev Benchmarks — Epoch AI (CC-BY 4.0)Elo — Arena Full attribution →