LLM Reference

GPT-5.2 vs o3

GPT-5.2 (2025) and o3 (2025) are frontier-tier reasoning models from OpenAI. GPT-5.2 ships a 400k-token context window, while o3 ships a 200k-token context window. On SWE-bench Verified, GPT-5.2 leads by 8.3 pts. On pricing, GPT-5.2 costs $1.75/1M input tokens versus $2/1M 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.

Pick GPT-5.2 for coding; o3 is better when coding workflow support matters more.

Decision scorecard

Local evidence first
SignalGPT-5.2o3
Best forreasoning-heavy apps, multimodal apps, and tool-calling agentsreasoning-heavy apps, multimodal apps, and tool-calling agents
Decision fitCoding, RAG, and AgentsCoding, RAG, and Agents
Context window400k200k
Cheapest output$14/1M tokens$8/1M tokens
Provider routes3 tracked3 tracked
Shared benchmarksSWE-bench Verified leader2 shared

Decision tradeoffs

Choose GPT-5.2 when...
  • GPT-5.2 holds a shared-benchmark lead on SWE-bench Verified, ahead by 8.3 points.
  • GPT-5.2 has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Local decision data tags GPT-5.2 for Coding, RAG, and Agents.
Choose o3 when...
  • o3 has the lower cheapest tracked output price at $8/1M tokens.
  • Local decision data tags o3 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

GPT-5.2

$4,900

Cheapest tracked route/tier: Replicate API

o3

$3,600

Cheapest tracked route/tier: OpenAI API

Estimated monthly gap: $1,300. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

GPT-5.2 -> o3
  • Provider overlap exists on OpenRouter and Vercel AI Gateway; start route-level A/B tests there.
  • o3 is $6/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
o3 -> GPT-5.2
  • Provider overlap exists on OpenRouter and Vercel AI Gateway; start route-level A/B tests there.
  • GPT-5.2 is $6/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.

Specs

Specification
Released2025-12-112025-04-16
Context window400k200k
Parameters
ArchitectureDecoder OnlyDecoder Only
LicenseProprietaryProprietary
OpennessProprietaryProprietary
WeightsNot releasedNot released
CodeUnknownUnknown
Commercial useCommercial use: conditionalCommercial use: conditional
Knowledge cutoff2025-082024-06

Pricing and availability

Pricing attributeGPT-5.2o3
Input price$1.75/1M tokens$2/1M tokens
Output price$14/1M tokens$8/1M tokens
Providers

Capabilities

CapabilityGPT-5.2o3
VisionYesYes
MultimodalYesYes
ReasoningYesYes
JSON / Tool useYesYes
Structured outputsYesYes
Code executionYesYes
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

BenchmarkGPT-5.2o3
SWE-bench Verified80.071.7
MMMU Pro79.576.4

Continue comparing

Last reviewed: 2026-06-29. Data sourced from public model cards and provider documentation.