o4-mini: Complete Specifications, Pricing, API Access & Use Cases (2026)
What is o4-mini?
o4-mini is OpenAI’s compact o-series reasoning model, released on April 16, 2025, featuring a 200,000-token context window and text-plus-image input for reasoning-heavy tasks, with API pricing of $1.10 per 1M input tokens, $0.275 per 1M cached input tokens, and $4.40 per 1M output tokens as of June 2026.
OpenAI describes o4-mini as a smaller model optimized for fast, reasoning with efficient performance in coding and visual tasks. It is part of the o-series reasoning family and is especially relevant for developers comparing cost, latency, context length, and multimodal input support. Teams already evaluating related OpenAI models such as GPT-4o, GPT-4o mini, and o3 often compare o4-mini when they need reasoning behavior at lower cost than larger reasoning models.
What Are o4-mini’s Key Specifications and Pricing?
The table below uses OpenAI’s official model documentation for provider specifications and pricing, and Gate.AI documentation for Gate.AI API compatibility and access mechanics.
| Field | Value |
|---|---|
| Provider | OpenAI (as of June 2026) |
| Model Family | OpenAI o-series reasoning models (as of June 2026) |
| Model Type | Compact reasoning model with text and image input (as of June 2026) |
| Release Date | April 16, 2025 (as of June 2026) |
| Context Window | 200,000 tokens (as of June 2026) |
| Max Output | 100,000 tokens (as of June 2026) |
| Input Pricing | $1.10 per 1M input tokens (as of June 2026) |
| Cached Input Pricing | $0.275 per 1M cached input tokens (as of June 2026) |
| Output Pricing | $4.40 per 1M output tokens (as of June 2026) |
| Pricing Unit | Per 1M text tokens (as of June 2026) |
| Modality Support | Text input/output; image input only (as of June 2026) |
| Supported Input Types | Text, image (as of June 2026) |
| Supported Output Types | Text (as of June 2026) |
| API Access | OpenAI API; Gate.AI OpenAI-compatible API using the user-provided model ID openai/o4-mini (as of June 2026) |
| Model ID | OpenAI: o4-mini; Gate.AI user-provided ID: openai/o4-mini (as of June 2026) |
| Availability | OpenAI API model page lists o4-mini; Gate.AI model ID was provided by the user, while Gate.AI docs verify OpenAI-compatible access (as of June 2026) |
| Knowledge Cutoff | June 1, 2024 (as of June 2026) |
| Rate Limits | Usage-tier dependent; OpenAI lists tiered RPM/TPM limits (as of June 2026) |
| Fine-tuning Support | Supported in OpenAI model documentation (as of June 2026) |
| Streaming Support | Supported in OpenAI model documentation and Gate.AI chat completions documentation (as of June 2026) |
| Batch API Support | OpenAI lists Batch endpoint support (as of June 2026) |
| Tool / Function Calling | Supported in OpenAI model documentation (as of June 2026) |
| Structured Output / JSON Mode | Structured outputs supported in OpenAI model documentation (as of June 2026) |
| License / Usage Restrictions | Governed by OpenAI and Gate.AI platform terms; model-specific license not separately specified in available official sources as of June 2026 |
What Can o4-mini Do That Makes It Useful in Production?
o4-mini is useful for reasoning-oriented production workflows where teams need multi-step analysis without always using a larger reasoning model. OpenAI positions it for math, coding, and visual tasks, while its 200K context window helps applications process long instructions, structured records, or multi-document prompts within a single request.
For developer workflows, o4-mini can support code analysis, debugging assistance, function calling, and structured outputs. This makes it relevant for code review assistants, issue triage, data transformation, and agentic workflows that need predictable response formats. It still requires validation, tests, and human review before deployment in production systems.
For multimodal reasoning, o4-mini accepts image input and can produce text output. This can help with chart interpretation, screenshot analysis, document-image review, and visual debugging. However, audio and video are not supported modalities for this model as of June 2026.
For cost-aware workloads, o4-mini may fit high-volume reasoning tasks because its token pricing is lower than o3’s listed pricing. A related alternative such as Gemini 2.0 Flash may also be relevant when teams prioritize different latency, modality, or provider requirements.
What Are o4-mini’s Supported Modalities?
| Modality | Supported? | Notes | Source Status |
|---|---|---|---|
| Text input | Yes | Used for prompts, instructions, documents, code, and structured text | OpenAI official docs, as of June 2026 |
| Text output | Yes | Primary output modality | OpenAI official docs, as of June 2026 |
| Image input | Yes | Useful for visual reasoning, charts, screenshots, and diagrams | OpenAI official docs, as of June 2026 |
| Image output | No | Not listed as an o4-mini output modality | OpenAI official docs, as of June 2026 |
| Audio input/output | No | Not supported for o4-mini | OpenAI official docs, as of June 2026 |
| Video input/output | No | Not supported for o4-mini | OpenAI official docs, as of June 2026 |
Where Does o4-mini Fall Short?
o4-mini is not a general audio, video, or image-generation model. OpenAI lists text output, text input, and image input, while audio and video are not supported for this model as of June 2026.
Its knowledge cutoff is June 1, 2024, so current events, prices, laws, product availability, and fast-changing technical details require retrieval, browsing, or external data grounding. This is a general AI limitation and is not unique to o4-mini unless stated by the provider.
Like other reasoning models, o4-mini can still produce incorrect answers, unsupported assumptions, or plausible but false explanations. High-stakes legal, medical, financial, security, or compliance usage should include expert review, testing, logging, and safety controls.
OpenAI’s documentation also notes that o4-mini is succeeded by GPT-5 mini. That does not make o4-mini unusable, but teams should review current availability, pricing, deprecation status, and migration options before building long-term systems around it.
What Is o4-mini Best Used For?
| Use Case | Why o4-mini May Fit | Important Limitation |
|---|---|---|
| Coding assistance | Useful for code reasoning, debugging, structured outputs, and function calling | Generated code needs tests and review |
| Visual reasoning | Supports image input for screenshots, charts, and diagrams | Produces text output only |
| Long-context analysis | 200K context window supports larger prompts and documents | Long context can increase cost and latency |
| Cost-aware reasoning | Lower listed token price than o3 | May not match larger models on the hardest tasks |
| Agent workflows | Supports streaming, function calling, and structured outputs | Requires guardrails, observability, and tool validation |
How Does o4-mini Compare to o3 and o3-mini?
| Comparison Area | o4-mini | o3 | o3-mini | Scenario Fit |
|---|---|---|---|---|
| Model role | Compact reasoning model | Larger reasoning model for complex tasks | Earlier small reasoning model | Choose by reasoning depth, cost, and modality needs |
| Context window | 200K tokens | 200K tokens | 200K tokens | Similar long-context ceiling across these models |
| Input modalities | Text and image | Text and image | Text only | o4-mini fits image-input reasoning better than o3-mini |
| Output modalities | Text | Text | Text | All three are text-output models |
| Input price | $1.10 / 1M tokens | $2.00 / 1M tokens | $1.10 / 1M tokens | o4-mini may fit cost-sensitive reasoning compared with o3 |
| Output price | $4.40 / 1M tokens | $8.00 / 1M tokens | $4.40 / 1M tokens | o4-mini and o3-mini have similar listed output pricing |
| Fine-tuning | Supported | Not supported | Not supported | o4-mini may fit customization workflows if fine-tuning is required |
| Comparison note | Efficient reasoning with image input | More capable but higher listed price | Text-only small reasoning model | No universal winner; select by workload constraints |
Comparison values are based on OpenAI model documentation as of June 2026.
How Do I Access o4-mini Through Gate.AI?
Gate.AI provides an OpenAI-compatible API format with the base URL https://api.gate.ai/openai/v1, bearer-token authentication, and a chat completions endpoint at POST /chat/completions. Gate.AI documentation also describes one API key, smart routing, API key creation, pay-as-you-go pricing, API key management, usage insights, and organization permissions.
For this page, the Gate.AI model ID is taken from the user-provided identifier openai/o4-mini. Gate.AI’s public models page was checked, but the rendered search result did not expose a specific o4-mini row. The executable examples below therefore rely on Gate.AI’s verified OpenAI-compatible API details and the user-provided model ID.
Python Example
from openai import OpenAIimport osclient = OpenAI(api_key=os.environ["GATEAI_API_KEY"],base_url="https://api.gate.ai/openai/v1",)response = client.chat.completions.create(model="openai/o4-mini",messages=[{"role": "user", "content": "Explain the difference between cached input and output tokens."}],)print(response.choices[0].message.content)
curl Example
curl https://api.gate.ai/openai/v1/chat/completions \-H "Authorization: Bearer $GATEAI_API_KEY" \-H "Content-Type: application/json" \-d '{"model": "openai/o4-mini","messages": [{"role": "user","content": "Explain the difference between cached input and output tokens."}]}'
Through Gate.AI, developers can use OpenAI-compatible tooling while managing access through Gate.AI account-level API keys, routing settings, usage insights, and organization controls where those features are enabled in the relevant plan.
FAQs
What is o4-mini’s context window?
o4-mini has a 200,000-token context window as listed in OpenAI’s model documentation as of June 2026.
How much does o4-mini cost?
OpenAI lists o4-mini at $1.10 per 1M input tokens, $0.275 per 1M cached input tokens, and $4.40 per 1M output tokens as of June 2026.
Can User access o4-mini through Gate.AI?
Gate.AI’s OpenAI-compatible API details are verified, and via Gate.AI model ID openai/o4-mini.
What is o4-mini useful for?
o4-mini is suitable for cost-aware reasoning, coding assistance, structured outputs, long-context analysis, and image-input reasoning. It should still be tested and monitored before production use.


