ZMIME
Comparison · 3 models · Updated Oct 4, 2026

Gemini 2.0 Flash vs Grok 4.20 (Reasoning) vs Kimi K2.6

Grok 4.20 (Reasoning) comes out ahead, 78 to 74 and 65 on our weighted score, and it is the cheaper option too.

  1. Google

    Gemini 2.0 Flash

    Released Dec 11, 2024

    65/100
    • ECI134.7
    • Price—
    • Context1.05M
  2. Our pick

    xAI

    Grok 4.20 (Reasoning)

    Released Mar 9, 2026

    78/100
    • ECI152.0
    • Price$1.25 / $2.50
    • Context1M
  3. Moonshot AI

    Kimi K2.6

    Released Apr 21, 2026

    74/100
    • ECI151.1
    • Price$0.95 / $4.00
    • Context262K
01 — Verdict

Grok 4.20 (Reasoning) is our pick

Grok 4.20 (Reasoning) is the better all-round choice, scoring 78/100 against Kimi K2.6 (74) and Gemini 2.0 Flash (65). Gemini 2.0 Flash wins on inputs & features. The score weighs capability 67%, inputs & features 20%, context window 13%.

  • CapabilityGrok 4.20 (Reasoning)Capabilities Index (ECI): Grok 4.20 (Reasoning) 152.0 · Kimi K2.6 151.1 · Gemini 2.0 Flash 134.7
  • Lowest priceGrok 4.20 (Reasoning)Grok 4.20 (Reasoning) $1.56 · Kimi K2.6 $1.71 per 1M tokens (3:1 blend) · Gemini 2.0 Flash unpriced
  • Longest contextGemini 2.0 FlashGemini 2.0 Flash 1,048,576 · Grok 4.20 (Reasoning) 1,000,000 · Kimi K2.6 262,144 tokens
  • Widest inputsGemini 2.0 FlashGemini 2.0 Flash: Text, Images, PDFs, Audio, Video · Grok 4.20 (Reasoning): Text, Images, PDFs · Kimi K2.6: Text, Images, Video
  • Self-hostingKimi K2.6Publishes downloadable weights
How the score is built
MeasureWeightGemini 2.0 FlashGrok 4.20 (Reasoning)Kimi K2.6
CapabilityCapabilities Index (ECI)67%598179
Inputs & features20%908080
Context window13%616037
Overall100%65/10078/10074/100

Left out because at least one model lacks the data: price. The remaining weights were rescaled.

02 — Side by side

Every spec in one table

Highlighted cells lead their row. Dashes mean the data is not published.

Gemini 2.0 Flash vs Grok 4.20 (Reasoning) vs Kimi K2.6 specifications side by side
SpecificationGemini 2.0 FlashGoogleGrok 4.20 (Reasoning)xAIKimi K2.6Moonshot AI
Capability
Capabilities Index (ECI)134.7152.0 (best)151.1
ECI rank#116 of 148#41 of 148 (best)#45 of 148
GPQA DiamondGraduate-level science questions—89.3%90.8% (best)
FrontierMath Tiers 1–3Research-level mathematics—44.9%57.2% (best)
OTIS Mock AIME 2024–2025Competition mathematics—92.2%96.1% (best)
SWE-bench VerifiedFixing real GitHub issues——76.7%
SimpleQA VerifiedShort factual questions—30.2%34.9% (best)
Price per million tokens
Input—$1.25$0.95 (best)
Output—$2.50 (best)$4.00
Cached input—$0.20$0.16 (best)
Blended (3:1)—$1.56 (best)$1.71
Long-context rate—Over 200K: $2.50 / $5.00Same rate
Price source—Official xAI APIOfficial Moonshot AI API
Limits
Context window1,048,576 tokens (best)1,000,000 tokens262,144 tokens
Max output8,192 tokens30,000 tokens262,144 tokens (best)
Inputs and features
TextYesYesYes
ImagesYesYesYes
PDFsYesYesNo
AudioYesNoNo
VideoYesNoYes
ReasoningNoYesYes
Tool callingYesYesYes
Structured outputYesYesYes
Availability
WeightsProprietaryProprietaryOpen
API model ID—grok-4.20-0309-reasoningkimi-k2.6
API providers—1146 (best)
ReleasedDec 11, 2024Mar 9, 2026Apr 21, 2026
Knowledge cutoffJun 2024—Jan 2025
03 — Cost

What would a month cost?

Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.

  • Gemini 2.0 Flash—
  • Grok 4.20 (Reasoning)$17.50
  • Kimi K2.6$17.50
04 — Questions

Which should you choose?

Which is better: Gemini 2.0 Flash, Grok 4.20 (Reasoning) or Kimi K2.6?

Grok 4.20 (Reasoning) is the better all-round choice, scoring 78/100 against Kimi K2.6 (74) and Gemini 2.0 Flash (65). Gemini 2.0 Flash wins on inputs & features. The score weighs capability 67%, inputs & features 20%, context window 13%.

Which is cheaper, Gemini 2.0 Flash, Grok 4.20 (Reasoning) or Kimi K2.6?

Grok 4.20 (Reasoning) is cheaper at $1.25 input / $2.50 output per million tokens (official xAI API price). Kimi K2.6 costs $0.95 input / $4.00 output per million tokens (official Moonshot AI API price). At a typical mix of three input tokens to one output token, that is $1.56 per million tokens for Grok 4.20 (Reasoning) versus $1.71 for Kimi K2.6 (1.1× as much). Gemini 2.0 Flash has no published per-token price.

Which scores higher on benchmarks?

Grok 4.20 (Reasoning) scores higher on the Capabilities Index (ECI): Grok 4.20 (Reasoning) 152.0 (#41 of 148), Kimi K2.6 151.1 (#45 of 148) and Gemini 2.0 Flash 134.7 (#116 of 148). The confidence ranges of the top two overlap (149.3–154.4 vs 149.1–152.8), so treat the gap as small.

Which is better for coding?

There are no published SWE-bench Verified results for Gemini 2.0 Flash and Grok 4.20 (Reasoning) yet, so there is no like-for-like coding score. On overall capability, Grok 4.20 (Reasoning) leads, which tends to carry over to coding, but test on your own codebase. All three support tool calling for agent workflows.

Which has the bigger context window?

Gemini 2.0 Flash has the largest context window at 1,048,576 tokens, against 1,000,000 for Grok 4.20 (Reasoning) and 262,144 for Kimi K2.6. Maximum output per response: Gemini 2.0 Flash up to 8,192, Grok 4.20 (Reasoning) up to 30,000, Kimi K2.6 up to 262,144 tokens.

Which can read images, PDFs, audio or video?

Gemini 2.0 Flash accepts text, images, PDFs, audio and video; Grok 4.20 (Reasoning) accepts text, images and PDFs; Kimi K2.6 accepts text, images and video. Gemini 2.0 Flash handles the widest range of inputs.

Are any of these open source?

Kimi K2.6 publishes its weights and can be self-hosted; Gemini 2.0 Flash and Grok 4.20 (Reasoning) is proprietary.

Which is newer?

Kimi K2.6 is the newest, released Apr 21, 2026. Grok 4.20 (Reasoning) came out Mar 9, 2026; Gemini 2.0 Flash came out Dec 11, 2024. Knowledge cutoff: Gemini 2.0 Flash Jun 2024, Kimi K2.6 Jan 2025.

How do you decide the winner?

Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.