Gemini 3.1 Pro vs Kimi K3.1 Pro

Google · US  |  Moonshot AI · China · Updated June 2026

Quick verdict

Pick Gemini 3.1 Pro for full multimodal input — text, image, audio and video in one 1m-token window or long video and document analysis. Pick Kimi K3.1 Pro for sparse moe with 2.8t total and about 104b active parameters, post-trained from the kimi k3 base or terminal-bench 4.0 of 65.7% (moonshot) and 67% as measured by artificial analysis.

Gemini 3.1 Pro (Google, US) and Kimi K3.1 Pro (Moonshot AI, China) line up two different AI ecosystems against each other — a comparison that is as much about cost philosophy and openness as raw capability. Gemini 3.1 Pro is a 1M-token multimodal workhorse — huge breadth across text, image, audio and video, but recall fades deep in the window. Kimi K3.1 Pro is moonshot's October 23, 2026 post-training upgrade to Kimi K3 - a 2.8T-parameter MoE at $2/$10 with open weights promised by November 4. The breakdown below works through their capabilities and ideal use cases so you can match one to your task.

Key differences at a glance

Side-by-side specs

SpecGemini 3.1 ProKimi K3.1 Pro
ProviderGoogle (US) Moonshot AI (China)
ReleasedFebruary 19, 2026 October 23, 2026
Context window1M (~1,573 pages) 1M tokens (~1,573 pages)
Price (in/out)$2/$12 per 1M tokens $2/$10 per 1M tokens
Open weight?No — API only No — API only
Modalitiestext, image, audio, video, code text, image, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1M26.3% Not published

Who wins what

Full multimodal input — text, image, audio and video in one 1M-token window

Gemini 3.1 Pro

Kimi K3.1 Pro is comparatively weak here — very high output-token use: roughly 150M output tokens across the Artificial Analysis index

Long video and document analysis

Gemini 3.1 Pro

Gemini 3.1 Pro lists long video and document analysis among its strengths; Kimi K3.1 Pro does not.

Agentic reasoning (high ARC-AGI-2)

Gemini 3.1 Pro

Gemini 3.1 Pro lists agentic reasoning (high ARC-AGI-2) among its strengths; Kimi K3.1 Pro does not.

Sparse MoE with 2.8T total and about 104B active parameters, post-trained from the Kimi K3 base

Kimi K3.1 Pro

Moonshot's October 23, 2026 post-training upgrade to Kimi K3 - a 2.8T-parameter MoE at $2/$10 with open weights promised by November 4 — and it is the newer of the two.

Terminal-Bench 4.0 of 65.7% (Moonshot) and 67% as measured by Artificial Analysis

Kimi K3.1 Pro

Kimi K3.1 Pro lists terminal-Bench 4.0 of 65.7% (Moonshot) and 67% as measured by Artificial Analysis among its strengths; Gemini 3.1 Pro does not.

Artificial Analysis Intelligence Index of 55, second only to Claude Opus 5.5 (58) among the models AI Weekly lists

Kimi K3.1 Pro

Kimi K3.1 Pro lists artificial Analysis Intelligence Index of 55, second only to Claude Opus 5.5 (58) among the models AI Weekly lists among its strengths; Gemini 3.1 Pro does not.

Which should you pick?

Anyone whose priority is full multimodal input — text, image, audio and video in one 1m-token window

→ Gemini 3.1 Pro

It is specifically built for that.

Anyone whose priority is sparse moe with 2.8t total and about 104b active parameters, post-trained from the kimi k3 base

→ Kimi K3.1 Pro

That is its strongest area.

An enterprise with regional data-residency rules

→ Gemini 3.1 Pro or Kimi K3.1 Pro

Origin (US vs China) affects where data is processed and which compliance regime applies — check the provider's terms for your region.

Gemini 3.1 Pro: where it fits

A 1M-token multimodal workhorse — huge breadth across text, image, audio and video, but recall fades deep in the window. Released February 19, 2026 by Google, it is built for full multimodal input — text, image, audio and video in one 1M-token window, long video and document analysis, agentic reasoning (high ARC-AGI-2), and broad multimodal understanding across formats.

Its trade-offs are real: long-context recall drops sharply past 256K (26.3% on MRCR v2 at 1M), premium price per token at $2/$12, and superseded within Google's own line by the newer 3.5/3.6 Flash releases for cost-sensitive work. At $2 in / $12 out per million tokens, it sits in the mid price band.

Kimi K3.1 Pro: where it fits

Moonshot's October 23, 2026 post-training upgrade to Kimi K3 - a 2.8T-parameter MoE at $2/$10 with open weights promised by November 4. Released October 23, 2026 by Moonshot AI, it is built for sparse MoE with 2.8T total and about 104B active parameters, post-trained from the Kimi K3 base, terminal-Bench 4.0 of 65.7% (Moonshot) and 67% as measured by Artificial Analysis, artificial Analysis Intelligence Index of 55, second only to Claude Opus 5.5 (58) among the models AI Weekly lists, and standard API price cut by a third versus K3 to $2/$10 per million tokens (Highspeed tier $4/$20).

Its trade-offs: weights promised by November 4, 2026 and not confirmed public as of November 3; license terms not yet disclosed, very high output-token use: roughly 150M output tokens across the Artificial Analysis index, self-hosting is impractical - about 1.4 TB of raw weights even at 4-bit, and most benchmarks are internal or use differing harnesses; no SWE-bench Verified figure published. At $2 in / $10 out per million tokens, it sits in the mid price band.

The bottom line for this matchup

This is less "which is smarter" and more "which ecosystem fits." Gemini 3.1 Pro (US) and Kimi K3.1 Pro (China) differ on pricing philosophy, data-residency, and tooling as much as on raw scores. The pragmatic move is to run one real task through both and judge the outputs against your own constraints — including where your data is allowed to be processed.

Want both Gemini 3.1 Pro and Kimi K3.1 Pro without two subscriptions? LumiChats gives you these plus 40+ models under one ₹69/day pass (about $1/day) — draft with one, cross-check with the other.

See pricing

Frequently asked questions

Is Gemini 3.1 Pro or Kimi K3.1 Pro better for coding?

Public SWE-Bench figures are not available for either model, so the honest test is your own repository — run an identical real bug through both. By design, Gemini 3.1 Pro leans toward full multimodal input — text, image, audio and video in one 1m-token window while Kimi K3.1 Pro leans toward sparse moe with 2.8t total and about 104b active parameters, post-trained from the kimi k3 base, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Gemini 3.1 Pro or Kimi K3.1 Pro?

They are priced almost identically, so cost will not decide between them.

Which has the bigger context window?

Both advertise 1M (~1,573 pages). Remember advertised ≠ usable: recall typically degrades before the ceiling.

Can I use both Gemini 3.1 Pro and Kimi K3.1 Pro together?

Yes — a multi-model platform like LumiChats gives you Gemini 3.1 Pro, Kimi K3.1 Pro and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.

Which is newer, Gemini 3.1 Pro or Kimi K3.1 Pro?

Kimi K3.1 Pro — released October 23, 2026, about 8 months after Gemini 3.1 Pro.

Related comparisons

Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.