OpenAI efficient reasoning model

GPT-5 Mini

A faster, lower-cost GPT-5 variant for well-defined tasks, precise prompts, and high-volume production workloads where intelligence per dollar matters.

Context window
400K
tokens
Max output
128K
tokens
Input
$0.25
per 1M tokens
Cached input
$0.025
per 1M tokens
Output
$2.00
per 1M tokens

01 / Overview

What GPT-5 Mini Is

GPT-5 Mini is the faster, more cost-efficient member of the original GPT-5 family, built for well-defined tasks and precise prompts where production throughput and token economics matter more than maximum model capability.

Intelligence Designed for Repetition at Scale

GPT-5 Mini occupies a different role from flagship and Pro models.

Instead of spending premium inference on the hardest possible problem, Mini targets workloads that need useful reasoning repeatedly: structured processing, focused analysis, application logic, extraction, classification, routing, concise generation, and other tasks with a clear definition of success.

That distinction matters in production. A small cost difference per request becomes substantial when an application executes millions of requests or uses a model repeatedly inside a workflow.

OpenAI describes GPT-5 Mini as strong intelligence for cost-sensitive, low-latency, high-volume workloads and specifically notes that it performs well on well-defined tasks with precise prompts.

Its 400K context window also means "Mini" describes the model's efficiency tier rather than a tiny context budget. Applications can still provide substantial documents, histories, retrieved evidence, and instructions.

GPT-5 Mini is now deprecated. For most new workloads in the same latency-and-volume category, OpenAI recommends GPT-5.6 Terra.

  • Lower-cost member of the GPT-5 family.
  • Optimized for well-defined and precisely prompted tasks.
  • Designed around cost-sensitive, high-volume production.
  • 400K context despite its efficiency positioning.
  • Deprecated in favor of newer efficient models.
Efficiency profile
Provider
OpenAI
Model
GPT-5 Mini
Positioning
Cost-efficient intelligence
Status
Deprecated
Knowledge cutoff
May 31, 2024
Input modalities
Text, Image
Output modality
Text

02 / Use cases

Where GPT-5 Mini Fit Best

GPT-5 Mini works best when a task is clear enough to specify precisely and frequent enough that latency and per-request cost become first-class engineering constraints.

Precise Tasks Benefit More Than Open-Ended Ambiguity

A high-volume model is most useful when the application knows what it wants.

For example, a workflow may need to classify support messages, extract a defined schema from documents, transform records into normalized text, route requests, summarize known fields, evaluate content against explicit criteria, or perform a focused reasoning step inside a larger agent.

These tasks can still require intelligence. They simply have tighter boundaries than open-ended research or a difficult multi-hour engineering problem.

GPT-5 Mini's economics also make it suitable for repeated substeps. An orchestration layer can reserve expensive models for difficult decisions while sending deterministic or well-scoped work to Mini.

Precise prompts are important. OpenAI explicitly describes the model as a strong fit for well-defined tasks and precise prompting, so vague objectives should be converted into explicit instructions, schemas, examples, or acceptance criteria.

High-volume patterns
  1. 01

    Structured extraction

    Turn documents or messages into known fields and schemas at a token price suitable for repeated production use.

  2. 02

    Classification and routing

    Assign categories, scores, destinations, or workflow branches when the decision criteria can be stated clearly.

  3. 03

    Focused generation

    Produce concise summaries, transformations, explanations, or application text from precise instructions.

  4. 04

    Agent subtasks

    Delegate bounded reasoning steps to a lower-cost model while reserving flagship inference for genuinely difficult decisions.

03 / Pricing

GPT-5 Mini Pricing

GPT-5 Mini costs $0.25 per million input tokens, $0.025 per million cached input tokens, and $2.00 per million output tokens, making token efficiency central to its production value.

Small Unit Costs Matter Most at Large Request Volumes

GPT-5 Mini's pricing makes the most sense when viewed through aggregate workload economics.

A single request may cost fractions of a cent. Multiply that request across a large customer base, batch pipeline, document collection, or multi-step workflow and model selection becomes a meaningful infrastructure decision.

Cached input is priced at one tenth of standard input. Repeated prompt prefixes, stable instructions, or recurring context can therefore materially reduce input cost when caching applies.

Output remains more expensive than input, so concise schemas and bounded generation are useful for both latency and spend.

For production evaluation, measure cost per completed business operation. A cheaper model that requires retries or frequent escalation may not be cheaper at the workflow level.

  • $0.25 per 1M input tokens.
  • $0.025 per 1M cached input tokens.
  • $2.00 per 1M output tokens.
  • Cached input is 10% of standard input price.
  • Evaluate effective cost after retries and fallback routing.
Scale-oriented pricing

1M tokens · USD

Input
$0.25
Cached input
$0.025
Output
$2.00

Example: 10K input + 2K output

Input cost
$0.0025
Output cost
$0.0040
Estimated total
$0.0065

04 / Context

A 400K Context Window in an Efficiency Tier

GPT-5 Mini combines its lower token price with a 400,000-token context window and up to 128,000 output tokens, allowing cost-sensitive workflows to operate on substantial working sets.

Mini Does Not Mean Short Context

The large context window expands the kinds of bounded tasks that can be handled without moving immediately to a flagship model.

An application can provide long source documents, multiple retrieved passages, conversation history, policy text, tool definitions, or a meaningful portion of a codebase while still using the Mini tier.

But capacity and necessity are different.

Sending more context increases token usage and can introduce irrelevant information. High-volume systems benefit from deliberate context selection because unnecessary tokens are multiplied across every request.

For RAG and document pipelines, evaluate retrieval quality alongside model quality. A smaller, focused context can improve both cost and signal-to-noise ratio.

The 128K output limit provides substantial generation headroom, although most Mini workloads should usually constrain output to the smallest format that satisfies the task.

Context capacity

Context window

400,000

Max output

128,000

Input contextOutput limit

Use the 400K window as capacity, not a target. High-volume workloads benefit from filtering context before every call.

05 / Reasoning

Reasoning for Bounded Production Tasks

GPT-5 Mini supports reasoning tokens, allowing the model to spend inference effort on tasks that require more than direct text generation while retaining its cost-efficient positioning.

Reasoning Should Match the Value of the Subtask

The model's strongest production role is not simply "cheap text."

Reasoning support allows GPT-5 Mini to handle tasks that involve interpretation, rule application, multi-step decisions, or structured analysis rather than only surface-level completion.

The engineering question is whether the task benefits enough from reasoning to justify the additional inference work.

For high-volume systems, this should be measured empirically. A reasoning configuration that improves accuracy by a small amount may be highly valuable for one workflow and unnecessary for another.

Use representative evaluation sets instead of assuming one reasoning policy should cover extraction, classification, generation, and agent subtasks equally.

Efficient reasoning
reasoning tokens

Bounded decision

Use reasoning when the model must interpret several constraints before producing a category, score, or structured result.

Throughput evaluation

Measure whether additional reasoning improves task success enough to justify its effect on latency and token consumption.

06 / Capabilities

Structured Outputs, Tools, and Multimodal Input

GPT-5 Mini supports streaming, function calling, structured outputs, text and image input, and both Responses and Chat Completions endpoints, giving efficient workloads a broad application integration surface.

Efficiency Still Comes with Production-Oriented Controls

Structured outputs are particularly valuable for Mini's target workloads.

Classification, extraction, routing, and workflow automation often need a stable machine-readable result rather than prose. Schema-constrained output reduces downstream parsing ambiguity and makes model behavior easier to validate.

Function calling lets GPT-5 Mini participate in tool-based application flows. This can include looking up data, invoking application actions, or handling a bounded subtask inside an orchestrated workflow.

Streaming is supported for interactive experiences where incremental output improves perceived latency.

The model accepts both text and image input while producing text output, which expands its use beyond text-only pipelines.

Fine-tuning and predicted outputs are not supported according to the official model card.

Production capabilities
  • Structured outputs

    Return schema-constrained results for extraction, classification, routing, and downstream application logic.

    Supported
  • Function calling

    Connect Mini to application tools and bounded agent workflows.

    Supported
  • Streaming

    Stream generated text for latency-sensitive interactive experiences.

    Supported
  • Image input

    Use images together with text as input while receiving text output.

    Supported
  • Fine-tuning

    The official GPT-5 Mini model card lists fine-tuning as unsupported.

    Not listed
  • Predicted outputs

    Predicted outputs are not supported.

    Not listed

07 / Evaluation

Strengths and Limitations

GPT-5 Mini's advantage is economical intelligence at production scale: it combines reasoning, structured output, tools, multimodal input, and a large context window at low token prices, but it is an older deprecated tier rather than the recommended starting point for new high-volume systems.

Where GPT-5 Mini stands out

  • Low token cost

    $0.25 input and $2 output per million tokens make repeated production inference substantially cheaper than flagship GPT-5 tiers.

  • High-volume fit

    OpenAI specifically positions the model for cost-sensitive, low-latency, high-volume workloads.

  • Large context capacity

    A 400K context window supports substantial source material despite the model's Mini positioning.

  • Structured application workflows

    Function calling and structured outputs make the model useful for machine-readable automation rather than only conversational text.

  • Precise-task specialization

    Well-defined prompts and clear success criteria align directly with the model's intended workload profile.

What to consider

  • Deprecated model

    OpenAI marks GPT-5 Mini as deprecated and recommends GPT-5.6 Terra for most new low-latency, high-volume workloads.

  • Older knowledge cutoff

    The official model card lists a May 31, 2024 knowledge cutoff.

  • Not the maximum-capability tier

    Hard, ambiguous, or high-stakes reasoning may justify escalation to a stronger model despite higher inference cost.

  • No fine-tuning

    Fine-tuning is not supported for GPT-5 Mini.

  • Snapshot migration deadline

    The dated gpt-5-mini-2025-08-07 snapshot is scheduled to shut down on December 11, 2026, with GPT-5.6 Terra as the recommended replacement.

Measure efficiency on your workload

Benchmark GPT-5 Mini before choosing a replacement

Run representative prompts through GPT-5 Mini and newer models, then compare output quality, token usage, cost, and task-level efficiency in EidoStack.

Start Free

For most new low-latency, high-volume workloads, OpenAI recommends starting with GPT-5.6 Terra.

Common Questions

What is GPT-5 Mini?

GPT-5 Mini is a faster, more cost-efficient version of GPT-5 designed for well-defined tasks, precise prompts, and cost-sensitive, low-latency, high-volume workloads.

Is GPT-5 Mini deprecated?

Yes. OpenAI currently marks GPT-5 Mini as deprecated.

What model does OpenAI recommend instead of GPT-5 Mini?

For most new low-latency, high-volume workloads, OpenAI recommends starting with GPT-5.6 Terra.

How much does GPT-5 Mini cost?

GPT-5 Mini costs $0.25 per 1M input tokens, $0.025 per 1M cached input tokens, and $2.00 per 1M output tokens.

What is the GPT-5 Mini context window?

GPT-5 Mini has a 400,000-token context window.

What is the maximum output of GPT-5 Mini?

GPT-5 Mini supports up to 128,000 output tokens.

What is the GPT-5 Mini knowledge cutoff?

The official model card lists May 31, 2024 as the knowledge cutoff.

Does GPT-5 Mini support reasoning?

Yes. OpenAI lists reasoning token support for GPT-5 Mini.

Does GPT-5 Mini support image input?

Yes. GPT-5 Mini supports text and image input and produces text output.

Does GPT-5 Mini support function calling?

Yes. Function calling is supported.

Does GPT-5 Mini support structured outputs?

Yes. The official model card lists structured outputs as supported.

Can GPT-5 Mini be fine-tuned?

No. The official model card lists fine-tuning as unsupported.

What kinds of workloads fit GPT-5 Mini?

The model is best suited to well-defined, precisely prompted workloads such as structured extraction, classification, routing, focused generation, and bounded agent subtasks where cost and throughput matter.

When will the GPT-5 Mini snapshot shut down?

OpenAI's deprecation schedule lists December 11, 2026 as the shutdown date for gpt-5-mini-2025-08-07.

What replaces gpt-5-mini-2025-08-07?

OpenAI recommends GPT-5.6 Terra as the replacement for the dated gpt-5-mini-2025-08-07 snapshot.

Model information

Last updated

The specifications, pricing, capabilities, positioning, and lifecycle information on this page are based on OpenAI's official GPT-5 Mini model documentation and API deprecation schedule.

GPT-5 Mini — Pricing, 400K Context & High-Volume AI | EidoStack