GPT-4.5 vs Kimi K3.1 Pro
Kimi K3.1 Pro leads the LLM Stats Score 55.5 to 19.6. Kimi K3.1 Pro is 23.4x cheaper per token.
OpenAI · Moonshot AI · Updated for 2026
Which is better?
Kimi K3.1 Pro leads the overall LLM Stats Score 55.5 to 19.6, ranking #5 overall.
In the 2 individual benchmarks reported for both models, Kimi K3.1 Pro wins 2; this is a narrower head-to-head signal than the composite indexes.
On price, Kimi K3.1 Pro is roughly 23.4x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Kimi K3.1 Pro also accepts a larger context window (1,048,576 input tokens), making it the stronger choice for long documents and large codebases.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose GPT-4.5
- you want predictable pricing at $75.00/M input and $150.00/M output
Choose Kimi K3.1 Pro
- overall performance matters — it scores 55.5 and ranks #5 on LLM Stats
- your work emphasizes reasoning and coding — it leads those capability indexes
- you value its reported benchmark strengths — it wins 2 of 2 exact shared results
- cost matters — it's about 23.4x cheaper per token
- you process long inputs — it offers a 1,048,576 token context window
- you want the most recent training data — it shipped Oct 2026
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
26 reported for GPT-4.5 · 30 for Kimi K3.1 Pro
GPT-4.5 outperforms in 0 benchmarks, while Kimi K3.1 Pro is better at 2 benchmarks (CharXiv-R, GPQA).
Kimi K3.1 Pro significantly outperforms across most benchmarks.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, GPT-4.5 ($75.00/1M tokens) is 37.5x more expensive than Kimi K3.1 Pro ($2.00/1M tokens).
For output processing, GPT-4.5 ($150.00/1M tokens) is 15.0x more expensive than Kimi K3.1 Pro ($10.00/1M tokens).
In conclusion, GPT-4.5 is more expensive than Kimi K3.1 Pro.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Kimi K3.1 Pro accepts 1,048,576 input tokens compared to GPT-4.5's 128,000 tokens. Kimi K3.1 Pro can generate longer responses up to 1,048,576 tokens, while GPT-4.5 is limited to 4,096 tokens.
Input capabilities
Documented input modalities across available providers
Both GPT-4.5 and Kimi K3.1 Pro support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
GPT-4.5
Kimi K3.1 Pro
Release Timeline
When each model was launched
GPT-4.5 was released on 2025-02-27, while Kimi K3.1 Pro was released on 2026-10-23.
Kimi K3.1 Pro is 20 months newer than GPT-4.5.
Feb 27, 2025
1.7 years ago
Oct 23, 2026
3 days ago
1.7yr newerKnowledge Cutoff
When training data ends
Neither model specifies a knowledge cutoff date.
Unable to compare the recency of their training data.
Provider Availability
GPT-4.5 is available from OpenAI. Kimi K3.1 Pro is available from Moonshot AI.
GPT-4.5
Kimi K3.1 Pro
Outputs Comparison
Judge for yourself.
Run your own prompts against GPT-4.5 and Kimi K3.1 Pro side-by-side, then vote on the output you prefer.
FAQ
Common questions about GPT-4.5 vs Kimi K3.1 Pro.