Model comparison · accepted catalogue facts 2026-10-21

Gemini 3.1 Pro Preview vs Kimi K2.6

A quality score or a computable price is missing. This pair has no better-and-cheaper verdict.

Editorial comparison: Context window divergence: Gemini 3.1 Pro Preview (Google) vs Kimi K2.6 (Moonshot AI) for long-document tasks Inclusion does not recommend either model.

Gemini 3.1 Pro Preview

LMArena general · Elo · higher is better

Scale starts at 1040 Elo

1480.3

Balanced effective USD / 1M tokens · lower is better

Unknown

Kimi K2.6

LMArena general · Elo · higher is better

Scale starts at 1040 Elo

1455.4

Balanced effective USD / 1M tokens · lower is better

$0.825/M

In-Depth Analysis

Gemini 3.1 Pro Preview vs Kimi K2.6: Measured Technical Breakdown

Comprehensive comparison across measured human-preference evaluation, effective production token costs, architectural limits, and migration trade-offs.

Measured Capability (LMArena)
Gemini 3.1 Pro Preview leads by 24.9 Elo

Gemini 3.1 Pro Preview: 1480.3 ±2.95 · Kimi K2.6: 1455.4 ±4.41 Statistically significant preference separation

Cost Comparison Across Canonical Production Workloads

Rates represent effective cost per 1M tokens under standard token blends. Cached prompt reads are factored according to workload context reuse.

Workload & RatioGemini 3.1 Pro PreviewKimi K2.6Cost DifferenceAdvantage
Balanced 3 tokens in per 1 outSeparately billed reasoning tokens are not part of this token blend.$0.825 /1M tokens—Custom quote needed
Summarise Huge input, tiny outputSeparately billed reasoning tokens are not part of this token blend.$0.410 /1M tokens—Custom quote needed
Chat Long cached system promptSeparately billed reasoning tokens are not part of this token blend.$0.929 /1M tokens—Custom quote needed
Code gen Output dominatesSeparately billed reasoning tokens are not part of this token blend.$1.32 /1M tokens—Custom quote needed
Agentic Context replayed each turnSeparately billed reasoning tokens are not part of this token blend.$0.434 /1M tokens—Custom quote needed

Architectural & Operational Specifications

SpecificationGemini 3.1 Pro PreviewKimi K2.6Operational Note
Context window1,048,576 tokens262,144 tokensGemini 3.1 Pro Preview has a 4.0× larger context window
Max output generation65,536 tokens235,929 tokensKimi K2.6 allows longer single-turn completions
Base input price$2.00 / 1M tokens$0.450 / 1M tokensKimi K2.6 input rate is cheaper
Base output price$12.00 / 1M tokens$1.95 / 1M tokensKimi K2.6 output rate is cheaper
Cached input price$0.200 / 1M tokens$0.045 / 1M tokensKimi K2.6 offers lower cached prompt cost
Reasoning & thinking tokensSupported; separately billed at $12.00/1MSupported; standard rates—
Input modalitiesaudio, file, image, text, videotext, image—
Tool calling / function useSupportedSupported—
Open weights & licenceProprietary (proprietary)Proprietary (API-only)Kimi K2.6 allows independent hosting or local deployment
Provider & reseller marketGoogle · 6 provider offersMoonshot AI · 17 provider offers (2.43× spread)—

When to Choose Gemini 3.1 Pro Preview

  • Higher measured general capability (1480.3 Elo on human evaluation).
  • Larger context window (1,048,576 tokens) for long-document or repo-level context.
  • Broader multimodal input support: audio, file, image, text, video.
  • Direct integration with Google tooling and API features.
Risks when moving from Kimi K2.6 → Gemini 3.1 Pro Preview:
  • Output limit: 235,929 → 65,536 tokens.

When to Choose Kimi K2.6

  • Higher maximum completion limit (235,929 tokens).
  • Direct integration with Moonshot AI tooling and API features.
Risks when moving from Gemini 3.1 Pro Preview → Kimi K2.6:
  • Context window: 1,048,576 → 262,144 tokens.
  • audio input is not supported by the candidate.
  • file input is not supported by the candidate.
  • video input is not supported by the candidate.

Compare · model decision

Choose two or three models

Inspect the differences, estimate your workload and keep the evidence. All standard catalogue models are available, including unrated ones.

Catalogue facts
2026-10-21

2 / 3 selected · 0 requirements
Open public comparison link
Public workload and requirements

These settings are included in the share link. The fixed-request scenario and private evaluation data below are excluded.

A ↔ B

A quality score or a computable price is missing. This pair has no better-and-cheaper verdict.

Estimated blend: 75% input, 25% output; 0% cached input. Base context tier. Prompt length selects the billing tier. An unlisted cache-read rate uses that tier’s full input rate in this blend; missing required input or output rates prevent an estimate. The fixed-request estimate below validates actual context and output limits and requires a published cache-read rate when cache hits are assumed.

What changes between these models

Quality first, then estimated price. LMArena scores are human-preference measurements, not a benchmark of your application. A missing score is unrated.

  • Gemini 3.1 Pro Preview · Meets the stated model requirements
  • Kimi K2.6 · Meets the stated model requirements
Material differences and unknown evidence. Deltas compare each model with model A. Unknown facts remain visible.
Measured factA Gemini 3.1 Pro PreviewB Kimi K2.6
LMArena general score (Elo)1,480.31,455.4Δ vs A: -24.9 Elo
Score interval half-width (± Elo)2.954.41Δ vs A: +1.46 Elo
LMArena document score (Elo)1,443.91,450.7Δ vs A: +6.8 Elo
Estimated effective USD / 1M tokensUnknown$0.825
Base input USD / 1M tokens$2$0.45Δ vs A: -1.55 USD/M
Base output USD / 1M tokens$12$1.95Δ vs A: -10.05 USD/M
Base cached-input USD / 1M tokens$0.2$0.045Δ vs A: -0.155 USD/M
Context window (tokens)1,048,576262,144Δ vs A: -786,432 tokens
Output limit (tokens)65,536235,929Δ vs A: +170,393 tokens
Input modalitiesaudio, file, image, text, videotext, image
Open weightsNot supportedUnknown
Recorded licenceproprietaryUnknown
Model providerGoogleMoonshot AI
Distinct sellers in the catalogue117Δ vs A: +16
Serving precision differs across offersNot supportedSupportedΔ vs A: +1
Recorded retirement dateUnknownUnknown
4 shared measured facts
Shared measured facts. Deltas compare each model with model A. Unknown facts remain visible.
Measured factA Gemini 3.1 Pro PreviewB Kimi K2.6
Benchmark reasoning effortdefaultdefault
Tool useSupportedSupportedΔ vs A: 0
ReasoningSupportedSupportedΔ vs A: 0
Retirement evidenceNone announced; not a guaranteeNone announced; not a guarantee

Provider counts and precision flags describe catalogue offers. They do not establish the precision, availability, region, tool behaviour or limits of your chosen endpoint. Open each model’s provider table before switching.

Complete price ladders and billing conditions

Gemini 3.1 Pro Preview

Estimate unavailable: Separately billed reasoning tokens are not part of this token blend.

Separate reasoning: $12/1M tokens; reasoning-token counts are not modelled here. Rates below are USD per 1M tokens. A threshold selects that whole input/output rate pair.

Input-token thresholdInputOutputCached input
Base, up to and including first threshold$2$12$0.2
> 200,000$4$18$0.4

Kimi K2.6

Rates below are USD per 1M tokens. A threshold selects that whole input/output rate pair.

Input-token thresholdInputOutputCached input
Base, up to and including first threshold$0.45$1.95$0.045
Migration preflight · compare each candidate with model A

Keeping Gemini 3.1 Pro Preview is a valid decision. No pairwise comparison certifies a drop-in replacement.

Gemini 3.1 Pro Preview → Kimi K2.6

Known loss or failed requirement

  • Context window: 1,048,576 → 262,144 tokens.
  • audio input is not supported by the candidate.
  • file input is not supported by the candidate.
  • video input is not supported by the candidate.
  • Provider endpoint, serving precision, availability and task success need your own verification. Catalogue model capabilities do not certify an endpoint.
Check alternatives to Gemini 3.1 Pro Preview

Estimate a fixed request shape

Private to this tab unless you save locally or explicitly export private details. These are estimates, not observed invoices. Cross-model token counts and task success are assumptions.

0.1 extra attempts means 10 extra full attempts per 100 requests. Cache writes, tool charges, taxes and unlisted charges are excluded.

  • Gemini 3.1 Pro PreviewEstimated total: unknown Separately billed reasoning tokens are not part of this request shape.
  • Kimi K2.6Estimated total: $1.875 1,000 full attempts · base rates
Prompt and output sensitivity · sampled scenarios

Every point recalculates the entire request shape. Tier-boundary samples include one token below, at and above each threshold. Ordering between samples is not guaranteed. Lowest known cost excludes unknown estimates and is not a replacement recommendation.

Vary input; hold output, requests, cache and retries fixed.
Input tokensGemini 3.1 Pro PreviewKimi K2.6Coverage
2,000unknownSeparately billed reasoning tokens are not part of this request shape.$1.875Lowest knownIncomplete
4,096unknownSeparately billed reasoning tokens are not part of this request shape.$2.8182Lowest knownIncomplete
32,768unknownSeparately billed reasoning tokens are not part of this request shape.$15.7206Lowest knownIncomplete
131,072unknownSeparately billed reasoning tokens are not part of this request shape.$59.9574Lowest knownIncomplete
199,999unknownSeparately billed reasoning tokens are not part of this request shape.$90.97455Lowest knownIncomplete
200,000unknownSeparately billed reasoning tokens are not part of this request shape.$90.975Lowest knownIncomplete
200,001unknownSeparately billed reasoning tokens are not part of this request shape.$90.97545Lowest knownIncomplete
Vary output; hold input, requests, cache and retries fixed.
Output tokensGemini 3.1 Pro PreviewKimi K2.6
128unknownSeparately billed reasoning tokens are not part of this request shape.$1.1496
2,048unknownSeparately billed reasoning tokens are not part of this request shape.$4.8936
8,192unknownSeparately billed reasoning tokens are not part of this request shape.$16.8744

Bring your observed evaluation results

JSON is parsed locally. Prompts, filenames, individual responses and extra fields are not retained. Import only aggregate measurements for selected models. Task/version labels do not establish that two evaluations used the same dataset.

Expected format
[{"model":"provider/exact-model-id","task":"support-answer","version":"rubric-1","attempts":100,"successes":84,"costUsd":2.4,"latencyMs":950}]

Use the exact catalogue ID. Replace the example values with observed measurements. Omit costUsd or latencyMs when they are unknown. No public score is inferred from these observations.

Keep the decision and its evidence

A portable record retains selected facts, complete tier ladders, public requirements and the publication manifest. It also embeds the full permitted public catalogue to verify the input artifact checksum. Files are larger for this reason (up to 2 MB); local storage is limited to 12 records. Team review is local to this browser; there is no hosted collaboration.

Saving is opt-in and includes private review fields. Shared comparison links never include them. Version 1 Check references remain separate and are not overwritten or guessed into this format.

Saved local decisions · 0

No version 2 decision records are stored in this browser.

Questions this page answers

Is Gemini 3.1 Pro Preview a better-and-cheaper replacement for Kimi K2.6?

A quality score or a computable price is missing. This pair has no better-and-cheaper verdict.

Which model is higher rated: Gemini 3.1 Pro Preview or Kimi K2.6?

Gemini 3.1 Pro Preview scores higher on LMArena general (1480.3 ±3.0) compared to Kimi K2.6 (1455.4 ±4.4), a margin of 24.9 Elo points. The measured confidence intervals do not overlap, demonstrating a statistically significant preference lead on human evaluations.

Which model is more cost-effective: Gemini 3.1 Pro Preview or Kimi K2.6?

Gemini 3.1 Pro Preview bills reasoning tokens separately. Direct pricing comparison requires evaluating your specific input/output prompt ratios and reasoning settings.

How do their context windows and generation limits compare?

Gemini 3.1 Pro Preview provides a 1,048,576-token context window with a maximum output limit of 65,536 tokens. Kimi K2.6 provides a 262,144-token context window with a maximum output of 235,929 tokens. Gemini 3.1 Pro Preview offers a 4.0× larger context capacity, making it suitable for larger repositories and multi-document workflows.

What capabilities are lost when switching between Gemini 3.1 Pro Preview and Kimi K2.6?

Switching from Gemini 3.1 Pro Preview to Kimi K2.6 involves: Context window: 1,048,576 → 262,144 tokens; audio input is not supported by the candidate; file input is not supported by the candidate; video input is not supported by the candidate. Conversely, moving from Kimi K2.6 to Gemini 3.1 Pro Preview involves: Output limit: 235,929 → 65,536 tokens. Run test suites on your specific prompt templates and tool declarations before cutting over production traffic.

Can Gemini 3.1 Pro Preview or Kimi K2.6 be self-hosted or deployed privately?

Both Gemini 3.1 Pro Preview and Kimi K2.6 are proprietary cloud models offered via managed API endpoints. Gemini 3.1 Pro Preview is served by Google and 6 catalogue offers, while Kimi K2.6 is served by Moonshot AI and 17 catalogue offers.

What is included in this comparison?

Accepted model capabilities, context and output limits, complete price-tier ladders, independent LMArena measurements and missing evidence. Provider endpoint precision and application success still need verification.

Can I compare a different workload or keep a decision record?

Yes. Change the public workload, prompt length and requirements in the comparison workspace. Fixed-request scenarios, aggregate evaluations and review notes stay local unless explicitly exported.

Evidence & Ask