ZMIME
Comparison · 3 models · Updated Oct 4, 2026

o4-mini vs o3 vs Gemini 2.5 Pro

Gemini 2.5 Pro comes out ahead, 63 to 59 and 58 on our weighted score, though o4-mini is 44% cheaper per token.

  1. OpenAI

    o4-mini

    Released Apr 16, 2025Deprecated

    59/100
    • ECI145.6
    • Price$1.10 / $4.40
    • Context200K
  2. OpenAI

    o3

    Released Apr 16, 2025

    58/100
    • ECI146.9
    • Price$2.00 / $8.00
    • Context200K
  3. Our pick

    Google

    Gemini 2.5 Pro

    Released Jun 17, 2025

    63/100
    • ECI145.3
    • Price$1.25 / $10.00
    • Context1.05M
01 — Verdict

Gemini 2.5 Pro is our pick

Gemini 2.5 Pro is the better all-round choice, scoring 63/100 against o4-mini (59) and o3 (58). It leads on inputs & features and context window. o4-mini wins on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • Capabilityo3Capabilities Index (ECI): o3 146.9 · o4-mini 145.6 · Gemini 2.5 Pro 145.3
  • Lowest priceo4-minio4-mini $1.93 · Gemini 2.5 Pro $3.44 · o3 $3.50 per 1M tokens (3:1 blend)
  • Longest contextGemini 2.5 ProGemini 2.5 Pro 1,048,576 · o4-mini 200,000 · o3 200,000 tokens
  • Widest inputsGemini 2.5 Proo4-mini: Text, Images · o3: Text, Images, PDFs · Gemini 2.5 Pro: Text, Images, PDFs, Audio, Video
  • Self-hostingNo open weightsAll three are available only through APIs
How the score is built
MeasureWeighto4-minio3Gemini 2.5 Pro
CapabilityCapabilities Index (ECI)50%737472
Price25%362424
Inputs & features15%7080100
Context window10%323261
Overall100%59/10058/10063/100
02 — Side by side

Every spec in one table

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

o4-mini vs o3 vs Gemini 2.5 Pro specifications side by side
Specificationo4-miniOpenAIo3OpenAIGemini 2.5 ProGoogle
Capability
Capabilities Index (ECI)145.6146.9 (best)145.3
ECI rank#76 of 148#63 of 148 (best)#78 of 148
GPQA DiamondGraduate-level science questions79.6%81.8%85.3% (best)
FrontierMath Tiers 1–3Research-level mathematics36.1% (best)33.3%24.6%
OTIS Mock AIME 2024–2025Competition mathematics81.7%84.4%84.7% (best)
SWE-bench VerifiedFixing real GitHub issues—62.3% (best)57.6%
SimpleQA VerifiedShort factual questions19.6%49.4% (best)—
Price per million tokens
Input$1.10 (best)$2.00$1.25
Output$4.40 (best)$8.00$10.00
Cached input$0.275$0.50$0.125 (best)
Blended (3:1)$1.93 (best)$3.50$3.44
Long-context rateSame rateSame rateOver 200K: $2.50 / $15.00
Price sourceOfficial OpenAI APIOfficial OpenAI APIOfficial Google API
Limits
Context window200,000 tokens200,000 tokens1,048,576 tokens (best)
Max output100,000 tokens (best)100,000 tokens (best)65,536 tokens
Inputs and features
TextYesYesYes
ImagesYesYesYes
PDFsNoYesYes
AudioNoNoYes
VideoNoNoYes
ReasoningYeslow · medium · highYeslow · medium · highYes
Tool callingYesYesYes
Structured outputYesYesYes
Availability
WeightsProprietaryProprietaryProprietary
API model IDo4-minio3gemini-2.5-pro
API providers191822 (best)
ReleasedApr 16, 2025Apr 16, 2025Jun 17, 2025
Knowledge cutoffMay 2024May 2024Jan 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.

  • o4-mini$19.80
  • o3$36.00
  • Gemini 2.5 Pro$32.50
04 — Questions

Which should you choose?

Which is better: o4-mini, o3 or Gemini 2.5 Pro?

Gemini 2.5 Pro is the better all-round choice, scoring 63/100 against o4-mini (59) and o3 (58). It leads on inputs & features and context window. o4-mini wins on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, o4-mini, o3 or Gemini 2.5 Pro?

o4-mini is cheaper at $1.10 input / $4.40 output per million tokens (official OpenAI API price). Gemini 2.5 Pro costs $1.25 input / $10.00 output per million tokens (official Google API price); o3 costs $2.00 input / $8.00 output per million tokens (official OpenAI API price). At a typical mix of three input tokens to one output token, that is $1.93 per million tokens for o4-mini versus $3.44 for Gemini 2.5 Pro (1.8× as much) and $3.50 for o3 (1.8× as much).

Which scores higher on benchmarks?

o3 scores higher on the Capabilities Index (ECI): o3 146.9 (#63 of 148), o4-mini 145.6 (#76 of 148) and Gemini 2.5 Pro 145.3 (#78 of 148). The confidence ranges of the top two overlap (144.9–148.6 vs 143.0–147.4), so treat the gap as small. On individual benchmarks: GPQA Diamond — Gemini 2.5 Pro 85.3%, o3 81.8%, o4-mini 79.6%; FrontierMath Tiers 1–3 — o4-mini 36.1%, o3 33.3%, Gemini 2.5 Pro 24.6%; OTIS Mock AIME 2024–2025 — Gemini 2.5 Pro 84.7%, o3 84.4%, o4-mini 81.7%.

Which is better for coding?

There are no published SWE-bench Verified results for o4-mini yet, so there is no like-for-like coding score. On overall capability, o3 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 2.5 Pro has the largest context window at 1,048,576 tokens, against 200,000 for o4-mini and 200,000 for o3. Maximum output per response: o4-mini up to 100,000, o3 up to 100,000, Gemini 2.5 Pro up to 65,536 tokens.

Which can read images, PDFs, audio or video?

o4-mini accepts text and images; o3 accepts text, images and PDFs; Gemini 2.5 Pro accepts text, images, PDFs, audio and video. Gemini 2.5 Pro handles the widest range of inputs.

Are any of these open source?

No. o4-mini, o3 and Gemini 2.5 Pro are proprietary and only available through APIs and apps.

Which is newer?

Gemini 2.5 Pro is the newest, released Jun 17, 2025. o4-mini came out Apr 16, 2025; o3 came out Apr 16, 2025. Knowledge cutoff: o4-mini May 2024, o3 May 2024, Gemini 2.5 Pro 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.