llmreference

Composer 2.5 vs GPT-5.4

Composer 2.5 (2026) and GPT-5.4 (2026) are agentic coding models from Cursor (Anysphere) and OpenAI. Composer 2.5 ships a not-yet-sourced context window, while GPT-5.4 ships a 1.1M-token context window. On pricing, Composer 2.5 costs $0.5/1M input tokens versus $2.5/1M for the alternative. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit. It focuses on practical selection signals rather than broad model-family marketing.

Composer 2.5 is ~400% cheaper at $0.5/1M; pay for GPT-5.4 only for coding workflow support.

Decision scorecard

Local evidence first
SignalComposer 2.5GPT-5.4
Decision fitCoding, Agents, and JSON / Tool useCoding, RAG, and Agents
Context window1.1M
Cheapest output$2.5/1M tokens$15/1M tokens
Provider routes1 tracked2 tracked
Shared benchmarks0 rows0 rows

Decision tradeoffs

Choose Composer 2.5 when...
  • Composer 2.5 has the lower cheapest tracked output price at $2.5/1M tokens.
  • Local decision data tags Composer 2.5 for Coding, Agents, and JSON / Tool use.
Choose GPT-5.4 when...
  • GPT-5.4 has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • GPT-5.4 has broader tracked provider coverage for fallback and procurement flexibility.
  • GPT-5.4 uniquely exposes Multimodal, Reasoning, and Structured outputs in local model data.
  • Local decision data tags GPT-5.4 for Coding, RAG, and Agents.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output prices on this page.

Lower estimate Composer 2.5

Composer 2.5

$1,025

Cheapest tracked route: Cursor

GPT-5.4

$5,750

Cheapest tracked route: OpenAI API

Estimated monthly gap: $4,725. Batch, cache, and negotiated pricing are excluded from this local estimate.

Switch friction

Composer 2.5 -> GPT-5.4
  • No overlapping tracked provider route is sourced for Composer 2.5 and GPT-5.4; plan for SDK, billing, or endpoint changes.
  • GPT-5.4 is $12.50/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • GPT-5.4 adds Multimodal, Reasoning, and Structured outputs in local capability data.
GPT-5.4 -> Composer 2.5
  • No overlapping tracked provider route is sourced for GPT-5.4 and Composer 2.5; plan for SDK, billing, or endpoint changes.
  • Composer 2.5 is $12.50/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Check replacement coverage for Multimodal, Reasoning, and Structured outputs before moving production traffic.

Specs

Specification
Released2026-05-182026-03-05
Context window1.1M
Parameters
Architecture-decoder only
LicenseProprietaryProprietary
Knowledge cutoff-2025-08

Pricing and availability

Pricing attributeComposer 2.5GPT-5.4
Input price$0.5/1M tokens$2.5/1M tokens
Output price$2.5/1M tokens$15/1M tokens
Providers

Capabilities

CapabilityComposer 2.5GPT-5.4
VisionNoNo
MultimodalNoYes
ReasoningNoYes
Function callingYesYes
Tool useYesYes
Structured outputsNoYes
Code executionYesYes

Benchmarks

No shared benchmark rows are currently sourced for this pair.

Deep dive

The capability footprint differs most on multimodal input: GPT-5.4, reasoning mode: GPT-5.4, and structured outputs: GPT-5.4. Both models share function calling, tool use, and code execution, 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, Composer 2.5 lists $0.5/1M input and $2.5/1M output tokens, while GPT-5.4 lists $2.5/1M input and $15/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Composer 2.5 lower by about $5.15 per million blended tokens. Availability is 1 providers versus 2, so concentration risk also matters.

Choose Composer 2.5 when coding workflow support and lower input-token cost are central to the workload. Choose GPT-5.4 when coding workflow support 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. This keeps the decision grounded in measurable tradeoffs instead of brand-level assumptions. It also helps separate model capability from provider packaging, which can change cost and latency.

FAQ

Which is cheaper, Composer 2.5 or GPT-5.4?

Composer 2.5 is cheaper on tracked token pricing. Composer 2.5 costs $0.5/1M input and $2.5/1M output tokens. GPT-5.4 costs $2.5/1M input and $15/1M output tokens. Provider discounts or batch pricing can still change the final bill.

Is Composer 2.5 or GPT-5.4 open source?

Composer 2.5 is listed under Proprietary. GPT-5.4 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 multimodal input, Composer 2.5 or GPT-5.4?

GPT-5.4 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.

Which is better for reasoning mode, Composer 2.5 or GPT-5.4?

GPT-5.4 has the clearer documented reasoning mode signal in this comparison. If reasoning mode is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Which is better for function calling, Composer 2.5 or GPT-5.4?

Both Composer 2.5 and GPT-5.4 expose function calling. 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 Composer 2.5 and GPT-5.4?

Composer 2.5 is available on Cursor. GPT-5.4 is available on OpenAI API and OpenRouter. Provider coverage can affect latency, region availability, compliance posture, and fallback options. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Continue comparing

Last reviewed: 2026-05-19. Data sourced from public model cards and provider documentation.