ZMIME
Comparison · 2 models · Updated Oct 4, 2026

o3 vs GPT-5.4 mini

GPT-5.4 mini comes out ahead, 63 to 58 on our weighted score, and it is the cheaper option too.

  1. OpenAI

    o3

    Released Apr 16, 2025

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

    OpenAI

    GPT-5.4 mini

    Released Mar 17, 2026

    63/100
    • ECI148.8
    • Price$0.75 / $4.50
    • Context400K
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01 — Verdict

GPT-5.4 mini is our pick

GPT-5.4 mini is the better all-round choice, scoring 63/100 against o3 (58). It leads on capability, price and context window. o3 wins on inputs & features. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityGPT-5.4 miniCapabilities Index (ECI): GPT-5.4 mini 148.8 · o3 146.9
  • Lowest priceGPT-5.4 miniGPT-5.4 mini $1.69 · o3 $3.50 per 1M tokens (3:1 blend)
  • Longest contextGPT-5.4 miniGPT-5.4 mini 400,000 · o3 200,000 tokens
  • Widest inputso3o3: Text, Images, PDFs · GPT-5.4 mini: Text, Images
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeighto3GPT-5.4 mini
CapabilityCapabilities Index (ECI)50%7477
Price25%2439
Inputs & features15%8070
Context window10%3244
Overall100%58/10063/100
02 — Side by side

Every spec in one table

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

o3 vs GPT-5.4 mini specifications side by side
Specificationo3OpenAIGPT-5.4 miniOpenAI
Capability
Capabilities Index (ECI)146.9148.8 (best)
ECI rank#63 of 148#56 of 148 (best)
GPQA DiamondGraduate-level science questions81.8%86.9% (best)
FrontierMath Tiers 1–3Research-level mathematics33.3%51.2% (best)
OTIS Mock AIME 2024–2025Competition mathematics84.4%88.9% (best)
SWE-bench VerifiedFixing real GitHub issues62.3%—
SimpleQA VerifiedShort factual questions49.4% (best)29.4%
Price per million tokens
Input$2.00$0.75 (best)
Output$8.00$4.50 (best)
Cached input$0.50$0.075 (best)
Blended (3:1)$3.50$1.69 (best)
Long-context rateSame rateSame rate
Price sourceOfficial OpenAI APIOfficial OpenAI API
Limits
Context window200,000 tokens400,000 tokens (best)
Max output100,000 tokens128,000 tokens (best)
Inputs and features
TextYesYes
ImagesYesYes
PDFsYesNo
AudioNoNo
VideoNoNo
ReasoningYeslow · medium · highYeslow · medium · high · xhigh
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model IDo3gpt-5.4-mini
API providers1829 (best)
ReleasedApr 16, 2025Mar 17, 2026
Knowledge cutoffMay 2024Aug 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.

  • o3$36.00
  • GPT-5.4 mini$16.50
04 — Questions

Which should you choose?

Which is better: o3 or GPT-5.4 mini?

GPT-5.4 mini is the better all-round choice, scoring 63/100 against o3 (58). It leads on capability, price and context window. o3 wins on inputs & features. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, o3 or GPT-5.4 mini?

GPT-5.4 mini is cheaper at $0.75 input / $4.50 output per million tokens (official OpenAI 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 $1.69 per million tokens for GPT-5.4 mini versus $3.50 for o3 (2.1× as much).

Which scores higher on benchmarks?

GPT-5.4 mini scores higher on the Capabilities Index (ECI): GPT-5.4 mini 148.8 (#56 of 148) and o3 146.9 (#63 of 148). The confidence ranges of the top two overlap (147.1–150.5 vs 144.9–148.6), so treat the gap as small. On individual benchmarks: GPQA Diamond — GPT-5.4 mini 86.9%, o3 81.8%; FrontierMath Tiers 1–3 — GPT-5.4 mini 51.2%, o3 33.3%; OTIS Mock AIME 2024–2025 — GPT-5.4 mini 88.9%, o3 84.4%; SimpleQA Verified — o3 49.4%, GPT-5.4 mini 29.4%.

Which is better for coding?

There are no published SWE-bench Verified results for GPT-5.4 mini yet, so there is no like-for-like coding score. On overall capability, GPT-5.4 mini leads, which tends to carry over to coding, but test on your own codebase. Both support tool calling for agent workflows.

Which has the bigger context window?

GPT-5.4 mini has the largest context window at 400,000 tokens, against 200,000 for o3. Maximum output per response: o3 up to 100,000, GPT-5.4 mini up to 128,000 tokens.

Which can read images, PDFs, audio or video?

o3 accepts text, images and PDFs; GPT-5.4 mini accepts text and images. o3 handles the widest range of inputs.

Are any of these open source?

No. o3 and GPT-5.4 mini are proprietary and only available through APIs and apps.

Which is newer?

GPT-5.4 mini is the newest, released Mar 17, 2026. o3 came out Apr 16, 2025. Knowledge cutoff: o3 May 2024, GPT-5.4 mini 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.