GPT-5.4 vs GPT-5.5 Instant
Pricing, benchmarks, and use case comparison
Quick take
- •GPT-5.4 is meaningfully stronger at long context (92 vs 80 on our capability index).
- •GPT-5.5 Instant is meaningfully stronger at speed (92 vs 66).
- •GPT-5.4 is 50% cheaper on input tokens, which compounds fast on high-volume or agentic workloads.
- •GPT-5.5 Instant has a 1050000 context window vs 1,050,000 tokens (128,000 max output) - better for whole-repo or long-document work.
Specs comparison
| GPT-5.4 | GPT-5.5 Instant | |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Type | Closed source | Closed source |
| Context window | 1,050,000 tokens (128,000 max output) | ✓1050000 |
| Input / 1M tokens | ✓$2.50 | 5.00 |
| Output / 1M tokens | $15.00 | 30.00 |
| Release date | 2026-03 | 2026-05 |
Benchmarks
| Benchmark | GPT-5.4 | GPT-5.5 Instant |
|---|---|---|
| AIME 2025 | - | 81.2 |
| Terminal-Bench 2.0 | - | 82.7 |
| FrontierMath Tier 1–3 | - | 51.7 |
Scores sourced from official provider release posts and independent benchmark aggregators.
Which should you choose?
Choose GPT-5.4 if...
- →Large-context tasks where GPT-5.5-level frontier reasoning is not required
- →Cost-conscious production workloads that still need strong capability
- →Migrating from GPT-5.4-based systems where behavior is already tuned
Choose GPT-5.5 Instant if...
- →Interactive chat and everyday assistant tasks where responsiveness matters most
- →High-volume, latency-sensitive workloads that do not need deep reasoning
- →General questions, drafting, and summarization at speed