Kimi K3.1 Pro vs Mercury 3
Kimi K3.1 Pro leads the LLM Stats Score 55.5 to 35.9. Mercury 3 is 24.6x cheaper per token.
Moonshot AI · Inception · Updated for 2026
Which is better?
Kimi K3.1 Pro leads the overall LLM Stats Score 55.5 to 35.9, ranking #5 overall.
In the 1 individual benchmarks reported for both models, Kimi K3.1 Pro wins 1; this is a narrower head-to-head signal than the composite indexes.
On price, Mercury 3 is roughly 24.6x 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 Kimi K3.1 Pro
- overall performance matters — it scores 55.5 and ranks #5 on LLM Stats
- your work emphasizes reasoning and agents — it leads those capability indexes
- you value its reported benchmark strengths — it wins 1 of 1 exact shared results
- you process long inputs — it offers a 1,048,576 token context window
- you want the most recent training data — it shipped Oct 2026
Choose Mercury 3
- cost matters — it's about 24.6x cheaper per token
At a glance
The differences that matter most.
Individual benchmarks
30 reported for Kimi K3.1 Pro · 12 for Mercury 3
Kimi K3.1 Pro outperforms in 1 benchmarks (GPQA), while Mercury 3 is better at 0 benchmarks.
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, Kimi K3.1 Pro ($2.00/1M tokens) is 20.0x more expensive than Mercury 3 ($0.10/1M tokens).
For output processing, Kimi K3.1 Pro ($10.00/1M tokens) is 28.6x more expensive than Mercury 3 ($0.35/1M tokens).
In conclusion, Kimi K3.1 Pro is more expensive than Mercury 3.*
* 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 Mercury 3's 1,000,000 tokens. Kimi K3.1 Pro can generate longer responses up to 1,048,576 tokens, while Mercury 3 is limited to 131,072 tokens.
Input capabilities
Documented input modalities across available providers
Kimi K3.1 Pro supports multimodal inputs, whereas Mercury 3 does not.
Kimi K3.1 Pro can handle both text and other forms of data like images, making it suitable for multimodal applications.
Kimi K3.1 Pro
Mercury 3
Release Timeline
When each model was launched
Kimi K3.1 Pro was released on 2026-10-23, while Mercury 3 was released on 2026-10-19.
Kimi K3.1 Pro is 0 month newer than Mercury 3.
Oct 23, 2026
6 days ago
4d newerOct 19, 2026
1 weeks ago
Knowledge Cutoff
When training data ends
Neither model specifies a knowledge cutoff date.
Unable to compare the recency of their training data.
Provider Availability
Kimi K3.1 Pro is available from Moonshot AI. Mercury 3 is available from Inception.
Kimi K3.1 Pro
Mercury 3
Outputs Comparison
Judge for yourself.
Run your own prompts against Kimi K3.1 Pro and Mercury 3 side-by-side, then vote on the output you prefer.
FAQ
Common questions about Kimi K3.1 Pro vs Mercury 3.