LLM Reference

GPT-5.2 vs o3 Mini

GPT-5.2 (2025) and o3 Mini (2025) are frontier-tier reasoning models from OpenAI. GPT-5.2 ships a 400k-token context window, while o3 Mini ships a 200k-token context window. On SWE-bench Verified, GPT-5.2 leads by 30.7 pts. On pricing, o3 Mini costs $1.10/1M input tokens versus $1.75/1M for the alternative. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.

o3 Mini is ~59% cheaper at $1.10/1M; pay for GPT-5.2 only for coding workflow support.

Decision scorecard

Local evidence first
SignalGPT-5.2o3 Mini
Best forreasoning-heavy apps, multimodal apps, and tool-calling agentsreasoning-heavy apps, tool-calling agents, and provider-routed production
Decision fitCoding, RAG, and AgentsCoding, RAG, and Agents
Context window400k200k
Cheapest output$14/1M tokens$4.40/1M tokens
Provider routes3 tracked4 tracked
Shared benchmarksSWE-bench Verified leader1 rows

Decision tradeoffs

Choose GPT-5.2 when...
  • GPT-5.2 holds a shared-benchmark lead on SWE-bench Verified, ahead by 30.7 points.
  • GPT-5.2 has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • GPT-5.2 uniquely exposes Vision and Multimodal in local model data.
  • Local decision data tags GPT-5.2 for Coding, RAG, and Agents.
Choose o3 Mini when...
  • o3 Mini has the lower cheapest tracked output price at $4.40/1M tokens.
  • o3 Mini has broader tracked provider coverage for fallback and procurement flexibility.
  • Local decision data tags o3 Mini for Coding, RAG, and Agents.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output route or tier on this page.

Lower estimate o3 Mini

GPT-5.2

$4,900

Cheapest tracked route/tier: Replicate API

o3 Mini

$1,980

Cheapest tracked route/tier: OpenRouter

Estimated monthly gap: $2,920. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

GPT-5.2 -> o3 Mini
  • Provider overlap exists on OpenRouter and Vercel AI Gateway; start route-level A/B tests there.
  • o3 Mini is $9.60/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Check replacement coverage for Vision and Multimodal before moving production traffic.
o3 Mini -> GPT-5.2
  • Provider overlap exists on OpenRouter and Vercel AI Gateway; start route-level A/B tests there.
  • GPT-5.2 is $9.60/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • GPT-5.2 adds Vision and Multimodal in local capability data.

Specs

Specification
Released2025-12-112025-01-31
Context window400k200k
Parameters
Architecturedecoder onlydecoder only
LicenseProprietaryProprietary
OpennessProprietaryProprietary
Commercial useCommercial use with conditionsCommercial use with conditions
Knowledge cutoff2025-082025-04

Pricing and availability

Pricing attributeGPT-5.2o3 Mini
Input price$1.75/1M tokens$1.10/1M tokens
Output price$14/1M tokens$4.40/1M tokens
Providers

Capabilities

CapabilityGPT-5.2o3 Mini
VisionYesNo
MultimodalYesNo
ReasoningYesYes
Function callingYesYes
Tool useYesYes
Structured outputsYesYes
Code executionYesYes
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

BenchmarkGPT-5.2o3 Mini
SWE-bench Verified80.049.3

Deep dive

On shared benchmark coverage, SWE-bench Verified has GPT-5.2 at 80 and o3 Mini at 49.3, with GPT-5.2 ahead by 30.7 points. The largest visible gap is 30.7 points on SWE-bench Verified, which matters most when that benchmark mirrors your workload. Treat isolated benchmark wins as directional, because provider routing, prompt style, and tool access can move real application results.

The capability footprint differs most on vision: GPT-5.2 and multimodal input: GPT-5.2. Both models share reasoning mode, function calling, tool use, and structured outputs, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.

For cost, GPT-5.2 lists $1.75/1M input and $14/1M output tokens on the cheapest tracked provider, while o3 Mini lists $1.10/1M input and $4.40/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts o3 Mini lower by about $3.33 per million blended tokens. Availability is 3 providers versus 4, so concentration risk also matters.

Choose GPT-5.2 when coding workflow support and larger context windows are central to the workload. Choose o3 Mini when coding workflow support, lower input-token cost, and broader provider choice are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.

FAQ

Which has a larger context window, GPT-5.2 or o3 Mini?

GPT-5.2 supports 400k tokens, while o3 Mini supports 200k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is cheaper, GPT-5.2 or o3 Mini?

o3 Mini is cheaper on tracked token pricing. GPT-5.2 costs $1.75/1M input and $14/1M output tokens. o3 Mini costs $1.10/1M input and $4.40/1M output tokens. Provider discounts or batch pricing can still change the final bill.

Is GPT-5.2 or o3 Mini open source?

GPT-5.2 is listed under Proprietary. o3 Mini is listed under Proprietary. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.

Which is better for vision, GPT-5.2 or o3 Mini?

GPT-5.2 has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is better for multimodal input, GPT-5.2 or o3 Mini?

GPT-5.2 has the clearer documented multimodal input signal in this comparison. If multimodal input is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Where can I run GPT-5.2 and o3 Mini?

GPT-5.2 is available on Replicate API, OpenRouter, and Vercel AI Gateway. o3 Mini is available on OpenRouter, Azure OpenAI, OpenAI API, and Vercel AI Gateway. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-06-04. Data sourced from public model cards and provider documentation.