GPT-5.4 Pro vs GPT-5.5 Instant
GPT-5.4 Pro (2026) and GPT-5.5 Instant (2026) are frontier reasoning models from OpenAI. GPT-5.4 Pro ships a 1.05m-token context window, while GPT-5.5 Instant ships a 400k-token context window. On pricing, GPT-5.4 Pro ranges from $30 to $60/1M input tokens by tier; GPT-5.5 Instant costs $5/1M 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-5.5 Instant is safer overall; choose GPT-5.4 Pro when coding workflow support matters.
Decision scorecard
Local evidence first| Signal | GPT-5.4 Pro | GPT-5.5 Instant |
|---|---|---|
| Best for | reasoning-heavy apps, multimodal apps, and tool-calling agents | multimodal apps and tool-calling agents |
| Decision fit | Coding, RAG, and Agents | Coding, RAG, and Agents |
| Context window | 1.05m | 400k |
| Cheapest output | $180/1M tokens | $30/1M tokens |
| Provider routes | 3 tracked | 1 tracked |
| Shared benchmarks | 0 shared | 0 shared |
Decision tradeoffs
- GPT-5.4 Pro has the larger context window for long prompts, retrieval packs, or transcript analysis.
- GPT-5.4 Pro has broader tracked provider coverage for fallback and route flexibility.
- GPT-5.4 Pro uniquely exposes Reasoning in local model data.
- Local decision data tags GPT-5.4 Pro for Coding, RAG, and Agents.
- GPT-5.5 Instant has the lower cheapest tracked output price at $30/1M tokens.
- Local decision data tags GPT-5.5 Instant 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.
GPT-5.4 Pro
$69,000
Cheapest tracked route/tier: OpenRouter
GPT-5.5 Instant
$11,500
Cheapest tracked route/tier: OpenAI API
Estimated monthly gap: $57,500. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.
Switch friction
- Provider overlap exists on OpenAI API; start route-level A/B tests there.
- GPT-5.5 Instant is $150/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- Check replacement coverage for Reasoning before moving production traffic.
- Provider overlap exists on OpenAI API; start route-level A/B tests there.
- GPT-5.4 Pro is $150/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
- GPT-5.4 Pro adds Reasoning in local capability data.
Specs
| Specification | ||
|---|---|---|
| Released | 2026-03-01 | 2026-05-05 |
| Context window | 1.05m | 400k |
| Parameters | — | — |
| Architecture | Decoder Only | Decoder Only |
| License | Proprietary | Proprietary |
| Openness | Proprietary | Proprietary |
| Weights | Not released | Not released |
| Code | Unknown | Unknown |
| Commercial use | Commercial use: conditional | Commercial use: conditional |
| Knowledge cutoff | 2025-08 | 2025-08 |
Pricing and availability
| Pricing attribute | GPT-5.4 Pro | GPT-5.5 Instant |
|---|---|---|
| Input price |
| $5/1M tokens |
| Output price |
| $30/1M tokens |
| Providers |
Capabilities
| Capability | GPT-5.4 Pro | GPT-5.5 Instant |
|---|---|---|
| Vision | Yes | Yes |
| Multimodal | Yes | Yes |
| Reasoning | Yes | No |
| JSON / Tool use | Yes | Yes |
| Structured outputs | Yes | Yes |
| Code execution | Yes | Yes |
| IDE integration | No | No |
| Computer use | No | No |
| Parallel agents | No | No |
Benchmarks
No shared benchmark scores are currently available for this pair.
Continue comparing
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- GPT-5.4 Pro vs GPT-5.5
Popular comparisons for GPT-5.4 Pro
Popular comparisons for GPT-5.5 Instant
Last reviewed: 2026-06-29. Data sourced from public model cards and provider documentation.