Skip to content
ModelCap

Head-to-head comparison

GPT-4o-mini vs o3

GPT-4o-mini (OpenAI) and o3 (OpenAI) compared on the ModelCap Index, API price, context window, provider availability, weight access and every public benchmark board they share. Figures are the same ones shown on the live rankings; nothing here is a hidden score.

Snapshot as of 22 September 2026

As of 22 September 2026, o3 holds the stronger ModelCap Index position (#53 vs #138); GPT-4o-mini is 13.3× cheaper per output token ($0.60/1M vs $8.00/1M); and o3 offers the longer context window (200K vs 128K tokens).

Which should you choose?

Choose GPT-4o-mini if…

  • API cost matters — $0.60/1M output tokens against $8.00/1M, about 13.3× cheaper.
  • your workload is prompt-heavy — input tokens cost $0.15/1M against $2.00/1M.
  • you want provider choice — 2 listed API providers against 1.

Choose o3 if…

  • you want the stronger overall ModelCap Index position — #53 against #138 (66.5 vs 40.0 points).
  • you need the longer context window — 200K tokens against 128K.
  • ARC-AGI-2 is your yardstick — 6.5% against 0.0%.
  • AA Humanity's Last Exam is your yardstick — 20.1% against 4.2%.
  • you want the more recently listed model — o3 was listed 16 April 2025, GPT-4o-mini 18 July 2024.

GPT-4o-mini vs o3: specs, pricing and context

Specification comparison of GPT-4o-mini and o3
FieldGPT-4o-miniOpenAIo3OpenAI
ModelCap Index position#138#53
Index score40.066.5
EvidenceMeasuredMeasured
Input price / 1M tokens$0.15$2.00
Output price / 1M tokens$0.60$8.00
Context window128K tokens200K tokens
Max output tokens16K100K
API providers listed21
Weight accessAPI onlyAPI only
Input modalitiesText, Image, FileImage, Text, File
First listed18 July 202416 April 2025
PublisherOpenAIOpenAI

Evidence: publisher-corpus-prior over 208 held-out anchors (59%); 1 specialist-board observation at 2.1% support (41%); shrunk 24.8 up toward the measured corpus · 3 public benchmark observations across 3 boards. Prices are the lowest listed API offer per million tokens observed on the OpenRouter catalogue.

Benchmark scores: GPT-4o-mini vs o3

Public benchmark boards where GPT-4o-mini or o3 has a published result
BoardGPT-4o-minio3Leads
Arena codingArena (LMArena)—14601454–1467Only one result
ARC-AGI-2ARC Prize Foundation0.0%6.5%Higho3
SWE-benchSWE-bench (Princeton / SWE-agent team)—58.4%Only one result
BFCL V4UC Berkeley (Gorilla)—63.1PromptOnly one result
AA τ²-Bench TelecomArtificial Analysis—80.7%tau2:telecom:dual-control:pass-at-1:3-repeats:source-model="o3":reasoning=trueOnly one result
AA Humanity's Last ExamArtificial Analysis4.2%hle:may-2025:text-only-2158:no-tools:pass-at-1:source-model="GPT-4o mini":reasoning=false20.1%hle:may-2025:text-only-2158:no-tools:pass-at-1:source-model="o3":reasoning=trueo3

Scores are the sources' own published figures for each model's best evaluated configuration; ModelCap never re-runs a benchmark.

Want a different pairing? Open the interactive comparison tool to swap either model for any current ranked language model.

GPT-4o-mini vs o3: common questions

Is GPT-4o-mini better than o3?

o3 ranks higher on the ModelCap Index as of 22 September 2026: #53 against #138. That is a capability ranking built from public benchmark evidence with published uncertainty; whether it is "better" for you also depends on price, context and where you can run it. Their published uncertainty intervals overlap, so the rank difference alone does not establish a reliable capability advantage for your workload.

Is GPT-4o-mini cheaper than o3?

GPT-4o-mini is cheaper on output tokens: $0.60/1M against $8.00/1M. Input tokens are $0.15/1M for GPT-4o-mini and $2.00/1M for o3. Prices are the lowest listed API offer ModelCap observed, in USD per million tokens. For 1,000 requests with 2,000 input and 500 output tokens each (2M input + 0.5M output), the listed-rate estimate is $0.60 for GPT-4o-mini versus $8.00 for o3. GPT-4o-mini costs 92.5% less in this scenario. This excludes caching, batch discounts, prompt-length tiers, tool charges and retries; verify the selected endpoint before budgeting.

Which has the bigger context window, GPT-4o-mini or o3?

o3 has the larger context window: 200K tokens against 128K.

Which is better for coding, GPT-4o-mini or o3?

The two models do not share a coding benchmark board on ModelCap yet, so no head-to-head coding score is published; the ModelCap Index position is the closest overall signal.

Are GPT-4o-mini and o3 open-weight models?

GPT-4o-mini: API only. o3: API only. Open weights mean the checkpoint can be downloaded and self-hosted under its licence; API-only models are available solely through hosted endpoints.

Where can I run GPT-4o-mini and o3?

ModelCap currently lists 2 API providers for GPT-4o-mini and 1 for o3, from the OpenRouter catalogue snapshot the site serves; each model page lists the providers and their prices.

How current is this GPT-4o-mini vs o3 comparison?

Every figure comes from the sealed ModelCap dataset published 22 September 2026; the page re-renders within a minute of each data refresh, and the ModelCap Index positions are the same ones shown on the live rankings.

Explore further