LLM Reference

GPT-5.4 Pro vs o3

GPT-5.4 Pro (2026) and o3 (2025) are frontier-tier reasoning models from OpenAI. GPT-5.4 Pro ships a 1.05m-token context window, while o3 ships a 200k-token context window. On pricing, GPT-5.4 Pro ranges from $30 to $60/1M input tokens by tier; o3 costs $2/1M input tokens. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.

GPT-5.4 Pro fits 5x more tokens; pick it for long-context work and o3 for tighter calls.

Decision scorecard

Local evidence first
SignalGPT-5.4 Proo3
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 window1.05m200k
Cheapest output$180/1M tokens$8/1M tokens
Provider routes3 tracked3 tracked
Shared benchmarks0 shared0 shared

Decision tradeoffs

Choose GPT-5.4 Pro when...
  • GPT-5.4 Pro has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Local decision data tags GPT-5.4 Pro 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-5.4 Pro

$69,000

Cheapest tracked route/tier: OpenRouter

o3

$3,600

Cheapest tracked route/tier: OpenAI API

Estimated monthly gap: $65,400. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

GPT-5.4 Pro -> o3
  • Provider overlap exists on OpenAI API, OpenRouter, and Vercel AI Gateway; start route-level A/B tests there.
  • o3 is $172/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
o3 -> GPT-5.4 Pro
  • Provider overlap exists on OpenRouter, OpenAI API, and Vercel AI Gateway; start route-level A/B tests there.
  • GPT-5.4 Pro is $172/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.

Specs

Specification
Released2026-03-012025-04-16
Context window1.05m200k
Parameters
ArchitectureDecoder OnlyDecoder Only
LicenseProprietaryProprietary
OpennessProprietaryProprietary
Commercial useCommercial use: conditionalCommercial use: conditional
Knowledge cutoff2025-082024-06

Pricing and availability

Pricing attributeGPT-5.4 Proo3
Input price
0-272,000t
$30/1M tokens
272,000t+
$60/1M tokens
$2/1M tokens
Output price
0-272,000t
$180/1M tokens
272,000t+
$270/1M tokens
$8/1M tokens
Providers

Capabilities

CapabilityGPT-5.4 Proo3
VisionYesYes
MultimodalYesYes
ReasoningYesYes
Function callingYesYes
Tool useYesYes
Structured outputsYesYes
Code executionYesYes
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

No shared benchmark scores are currently available for this pair.

Deep dive

The capability footprint is close: both models cover vision, multimodal input, reasoning mode, function calling, and tool use. That makes context budget, benchmark fit, and provider maturity more important than a simple checklist. If your application depends on one integration detail, verify it against the provider route you plan to use, not just the base model listing.

For cost, GPT-5.4 Pro lists tiered pricing: 0-272,000t is $30/1M input and $180/1M output; 272,000t+ is $60/1M input and $270/1M output, while o3 lists $2/1M input and $8/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts o3 lower by about $71.20 per million blended tokens. For tiered rows, this cheapest-track view can understate interactive or fast-lane spend, so compare the tier you will actually use. Availability is 3 providers versus 3, so concentration risk also matters.

Choose GPT-5.4 Pro when coding workflow support and larger context windows are central to the workload. Choose o3 when coding workflow support and lower input-token cost 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-5.4 Pro or o3?

GPT-5.4 Pro supports 1.05m tokens, while o3 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-5.4 Pro or o3?

GPT-5.4 Pro lists tiered pricing: 0-272,000t is $30/1M input and $180/1M output; 272,000t+ is $60/1M input and $270/1M output. o3 lists $2/1M input and $8/1M output tokens on the cheapest tracked provider. Compare the tier you will actually use; cheap async pricing can overstate savings for interactive workflows. Provider discounts or batch pricing can still change the final bill.

Is GPT-5.4 Pro or o3 open source?

GPT-5.4 Pro is listed under Proprietary. o3 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-5.4 Pro or o3?

Both GPT-5.4 Pro and o3 expose vision. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is better for multimodal input, GPT-5.4 Pro or o3?

Both GPT-5.4 Pro and o3 expose multimodal input. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Where can I run GPT-5.4 Pro and o3?

GPT-5.4 Pro is available on OpenRouter, OpenAI API, and Vercel AI Gateway. o3 is available on OpenAI API, OpenRouter, and Vercel AI Gateway. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-06-15. Data sourced from public model cards and provider documentation.