ZMIME
Comparison · 3 models · Updated Oct 4, 2026

Gemini 3 Pro Preview vs Gemini 3.5 Flash vs GPT-5.2

Too close to call on our weighted score (Gemini 3.5 Flash 69, Gemini 3 Pro Preview 67, GPT-5.2 61). The right pick depends on what you value most.

  1. Google

    Gemini 3 Pro Preview

    Released Nov 18, 2025

    67/100
    • ECI153.0
    • Price$2.00 / $12.00
    • Context1.05M
  2. Google

    Gemini 3.5 Flash

    Released May 19, 2026

    69/100
    • ECI154.5
    • Price$1.50 / $9.00
    • Context1.05M
  3. OpenAI

    GPT-5.2

    Released Dec 11, 2025

    61/100
    • ECI153.5
    • Price$1.75 / $14.00
    • Context400K
01 — Verdict

Too close to call

It is close. Our weighted score puts them within 2 points (Gemini 3.5 Flash 69/100, Gemini 3 Pro Preview 67/100, GPT-5.2 61/100), so choose by what matters most for your work: Gemini 3.5 Flash for raw capability. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityGemini 3.5 FlashCapabilities Index (ECI): Gemini 3.5 Flash 154.5 · GPT-5.2 153.5 · Gemini 3 Pro Preview 153.0
  • Lowest priceGemini 3.5 FlashGemini 3.5 Flash $3.38 · Gemini 3 Pro Preview $4.50 · GPT-5.2 $4.81 per 1M tokens (3:1 blend)
  • Longest contextGemini 3 Pro Preview and Gemini 3.5 FlashGemini 3 Pro Preview 1,048,576 · Gemini 3.5 Flash 1,048,576 · GPT-5.2 400,000 tokens
  • Widest inputsGemini 3 Pro Preview and Gemini 3.5 FlashGemini 3 Pro Preview: Text, Images, PDFs, Audio, Video · Gemini 3.5 Flash: Text, Images, PDFs, Audio, Video · GPT-5.2: Text, Images
  • Self-hostingNo open weightsAll three are available only through APIs
How the score is built
MeasureWeightGemini 3 Pro PreviewGemini 3.5 FlashGPT-5.2
CapabilityCapabilities Index (ECI)50%828483
Price25%192518
Inputs & features15%10010070
Context window10%616144
Overall100%67/10069/10061/100
02 — Side by side

Every spec in one table

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

Gemini 3 Pro Preview vs Gemini 3.5 Flash vs GPT-5.2 specifications side by side
SpecificationGemini 3 Pro PreviewGoogleGemini 3.5 FlashGoogleGPT-5.2OpenAI
Capability
Capabilities Index (ECI)153.0154.5 (best)153.5
ECI rank#39 of 148#33 of 148 (best)#38 of 148
GPQA DiamondGraduate-level science questions92.6%92.8% (best)91.4%
FrontierMath Tiers 1–3Research-level mathematics—62.8%67.4% (best)
OTIS Mock AIME 2024–2025Competition mathematics91.4%95.6%96.1% (best)
SWE-bench VerifiedFixing real GitHub issues72.9%79.3% (best)73.8%
SimpleQA VerifiedShort factual questions—66.2% (best)37.1%
Price per million tokens
Input$2.00$1.50 (best)$1.75
Output$12.00$9.00 (best)$14.00
Cached input—$0.15 (best)$0.175
Blended (3:1)$4.50$3.38 (best)$4.81
Long-context rateSame rateSame rateSame rate
Price sourceMedian of 2 providersOfficial Google APIOfficial OpenAI API
Limits
Context window1,048,576 tokens (best)1,048,576 tokens (best)400,000 tokens
Max output65,536 tokens65,536 tokens128,000 tokens (best)
Inputs and features
TextYesYesYes
ImagesYesYesYes
PDFsYesYesNo
AudioYesYesNo
VideoYesYesNo
ReasoningYesYesminimal · low · medium · highYeslow · medium · high · xhigh
Tool callingYesYesYes
Structured outputYesYesYes
Availability
WeightsProprietaryProprietaryProprietary
API model ID—gemini-3.5-flashgpt-5.2
API providers332 (best)21
ReleasedNov 18, 2025May 19, 2026Dec 11, 2025
Knowledge cutoffJan 2025Jan 2025Aug 31, 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 3 Pro Preview$44.00
  • Gemini 3.5 Flash$33.00
  • GPT-5.2$45.50
04 — Questions

Which should you choose?

Which is better: Gemini 3 Pro Preview, Gemini 3.5 Flash or GPT-5.2?

It is close. Our weighted score puts them within 2 points (Gemini 3.5 Flash 69/100, Gemini 3 Pro Preview 67/100, GPT-5.2 61/100), so choose by what matters most for your work: Gemini 3.5 Flash for raw capability. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, Gemini 3 Pro Preview, Gemini 3.5 Flash or GPT-5.2?

Gemini 3.5 Flash is cheaper at $1.50 input / $9.00 output per million tokens (official Google API price). Gemini 3 Pro Preview costs $2.00 input / $12.00 output per million tokens (median across 2 API providers); GPT-5.2 costs $1.75 input / $14.00 output per million tokens (official OpenAI API price). At a typical mix of three input tokens to one output token, that is $3.38 per million tokens for Gemini 3.5 Flash versus $4.50 for Gemini 3 Pro Preview (1.3× as much) and $4.81 for GPT-5.2 (1.4× as much).

Which scores higher on benchmarks?

Gemini 3.5 Flash scores higher on the Capabilities Index (ECI): Gemini 3.5 Flash 154.5 (#33 of 148), GPT-5.2 153.5 (#38 of 148) and Gemini 3 Pro Preview 153.0 (#39 of 148). The confidence ranges of the top two overlap (152.5–156.6 vs 151.7–155.4), so treat the gap as small. On individual benchmarks: GPQA Diamond — Gemini 3.5 Flash 92.8%, Gemini 3 Pro Preview 92.6%, GPT-5.2 91.4%; OTIS Mock AIME 2024–2025 — GPT-5.2 96.1%, Gemini 3.5 Flash 95.6%, Gemini 3 Pro Preview 91.4%; SWE-bench Verified — Gemini 3.5 Flash 79.3%, GPT-5.2 73.8%, Gemini 3 Pro Preview 72.9%.

Which is better for coding?

Gemini 3.5 Flash resolves more real GitHub issues on SWE-bench Verified: Gemini 3.5 Flash 79.3%, GPT-5.2 73.8% and Gemini 3 Pro Preview 72.9%. All three support tool calling for agent workflows.

Which has the bigger context window?

Gemini 3 Pro Preview and Gemini 3.5 Flash have the largest context windows (1,048,576 and 1,048,576 tokens), against 400,000 for GPT-5.2. Maximum output per response: Gemini 3 Pro Preview up to 65,536, Gemini 3.5 Flash up to 65,536, GPT-5.2 up to 128,000 tokens.

Which can read images, PDFs, audio or video?

Gemini 3 Pro Preview accepts text, images, PDFs, audio and video; Gemini 3.5 Flash accepts text, images, PDFs, audio and video; GPT-5.2 accepts text and images. Gemini 3 Pro Preview handles the widest range of inputs.

Are any of these open source?

No. Gemini 3 Pro Preview, Gemini 3.5 Flash and GPT-5.2 are proprietary and only available through APIs and apps.

Which is newer?

Gemini 3.5 Flash is the newest, released May 19, 2026. GPT-5.2 came out Dec 11, 2025; Gemini 3 Pro Preview came out Nov 18, 2025. Knowledge cutoff: Gemini 3 Pro Preview Jan 2025, Gemini 3.5 Flash Jan 2025, GPT-5.2 Aug 31, 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.