← Back to Model Hub/SIDE-BY-SIDE REVIEW
SHARE THIS:

GPT-5.5 Pro vs GPT-5 Pro

How do these models stack up? Below is an expert side-by-side comparison of specifications, context window capacity, live pricing per million tokens, and standardized benchmark scores for GPT-5.5 Pro and GPT-5 Pro.

OpenAI

GPT-5.5 Pro

GPT-5.5 Pro is OpenAI’s high-capability model optimized for deep reasoning and accuracy on complex, high-stakes workloads. It features a 1M+ token context window (922K input, 128K output) with support for...

View Full Specs
OpenAI

GPT-5 Pro

GPT-5 Pro is OpenAI’s most advanced model, offering major improvements in reasoning, code quality, and user experience. It is optimized for complex tasks that require step-by-step reasoning, instruction following, and...

View Full Specs

Technical Specifications

SpecificationGPT-5.5 ProGPT-5 Pro
ProviderOpenAIOpenAI
Context Window1,050,000 tokens400,000 tokens
Agent Suitability98/100N/A
Time to First Token (TTFT)450 msN/A
Deployment Modelmanaged apimanaged api
Production Stabilitybetastable
API AvailableYesYes
Released Date2026-04-242025-10-06

API Pricing Comparison

Input Price per Million Tokens

GPT-5.5 Pro

$30.00

GPT-5 Pro

$15.00

Output Price per Million Tokens

GPT-5.5 Pro

$180.00

GPT-5 Pro

$120.00

Want to test both models live?

Run side-by-side prompt prompts in our dynamic Sandbox. Check execution speeds, latency metrics, and compute actual costs in real-time.

Benchmark Performance Metrics

Scores show the raw performance percentages verified across key evaluation suites. Higher bars indicate superior accuracy and capability in that domain.

MMLUGeneral knowledge & multi-task understanding
9650.0%vsN/A
GPT-5.5 Pro
GPT-5 Pro
HumanEvalPython coding & logic synthesis
9820.0%vsN/A
GPT-5.5 Pro
GPT-5 Pro
MATHComplex mathematical problem solving
9600.0%vsN/A
GPT-5.5 Pro
GPT-5 Pro
GPQAGraduate-level expert reasoning
8910.0%vsN/A
GPT-5.5 Pro
GPT-5 Pro
HellaSwagCommonsense reasoning and inference
9940.0%vsN/A
GPT-5.5 Pro
GPT-5 Pro
MT-BenchMulti-turn conversation flow quality
990.0%vsN/A
GPT-5.5 Pro
GPT-5 Pro

GPT-5.5 Pro Quirks & Gotchas

  • Best-in-class instruction following for complex agentic chains
  • Premium pricing — use GPT-5 for cost-sensitive workloads

GPT-5 Pro Quirks & Gotchas

No developer gotchas reported.