ZMIME
Comparison · 3 models · Updated Oct 4, 2026

Gemini 3.5 Flash vs Gemini 3 Pro Preview 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 3.5 Flash

    Released May 19, 2026

    69/100
    • ECI154.5
    • Price$1.50 / $9.00
    • Context1.05M
  2. Google

    Gemini 3 Pro Preview

    Released Nov 18, 2025

    67/100
    • ECI153.0
    • Price$2.00 / $12.00
    • 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 3.5 Flash and Gemini 3 Pro PreviewGemini 3.5 Flash 1,048,576 · Gemini 3 Pro Preview 1,048,576 · GPT-5.2 400,000 tokens
  • Widest inputsGemini 3.5 Flash and Gemini 3 Pro PreviewGemini 3.5 Flash: Text, Images, PDFs, Audio, Video · Gemini 3 Pro Preview: 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 3.5 FlashGemini 3 Pro PreviewGPT-5.2
CapabilityCapabilities Index (ECI)50%848283
Price25%251918
Inputs & features15%10010070
Context window10%616144
Overall100%69/10067/10061/100
02 — Side by side

Every spec in one table

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

Gemini 3.5 Flash vs Gemini 3 Pro Preview vs GPT-5.2 specifications side by side
SpecificationGemini 3.5 FlashGoogleGemini 3 Pro PreviewGoogleGPT-5.2OpenAI
Capability
Capabilities Index (ECI)154.5 (best)153.0153.5
ECI rank#33 of 148 (best)#39 of 148#38 of 148
GPQA DiamondGraduate-level science questions92.8% (best)92.6%91.4%
FrontierMath Tiers 1–3Research-level mathematics62.8%—67.4% (best)
OTIS Mock AIME 2024–2025Competition mathematics95.6%91.4%96.1% (best)
SWE-bench VerifiedFixing real GitHub issues79.3% (best)72.9%73.8%
SimpleQA VerifiedShort factual questions66.2% (best)—37.1%
Price per million tokens
Input$1.50 (best)$2.00$1.75
Output$9.00 (best)$12.00$14.00
Cached input$0.15 (best)—$0.175
Blended (3:1)$3.38 (best)$4.50$4.81
Long-context rateSame rateSame rateSame rate
Price sourceOfficial Google APIMedian of 2 providersOfficial 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
ReasoningYesminimal · low · medium · highYesYeslow · medium · high · xhigh
Tool callingYesYesYes
Structured outputYesYesYes
Availability
WeightsProprietaryProprietaryProprietary
API model IDgemini-3.5-flash—gpt-5.2
API providers32 (best)321
ReleasedMay 19, 2026Nov 18, 2025Dec 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 3.5 Flash$33.00
  • Gemini 3 Pro Preview$44.00
  • GPT-5.2$45.50
04 — Questions

Which should you choose?

Which is better: Gemini 3.5 Flash, Gemini 3 Pro Preview 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 3.5 Flash, Gemini 3 Pro Preview 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 3.5 Flash and Gemini 3 Pro Preview 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 3.5 Flash up to 65,536, Gemini 3 Pro Preview up to 65,536, GPT-5.2 up to 128,000 tokens.

Which can read images, PDFs, audio or video?

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

Are any of these open source?

No. Gemini 3.5 Flash, Gemini 3 Pro Preview 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 3.5 Flash Jan 2025, Gemini 3 Pro Preview 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.