GPT-5.5 Instant vs GPT-6 Rosalind
Comparing GPT-5.5 Instant and GPT-6 Rosalind across benchmarks, pricing, and capabilities.
OpenAI · OpenAI · Updated for 2026
Which is better?
GPT-5.5 Instant and GPT-6 Rosalind trade strengths across price, capabilities, and technical limits. The better choice depends on the workload.
On price, GPT-5.5 Instant is roughly 2.7x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose GPT-5.5 Instant
- cost matters — it's about 2.7x cheaper per token
Choose GPT-6 Rosalind
- you want the most recent training data — it shipped Oct 2026
At a glance
The differences that matter most.
Individual benchmarks
9 reported for GPT-5.5 Instant · 0 for GPT-6 Rosalind
GPT-5.5 Instant and GPT-6 Rosalinddon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, GPT-5.5 Instant ($5.00/1M tokens) is 3.0x cheaper than GPT-6 Rosalind ($15.00/1M tokens).
For output processing, GPT-5.5 Instant ($30.00/1M tokens) is 2.5x cheaper than GPT-6 Rosalind ($75.00/1M tokens).
In conclusion, GPT-6 Rosalind is more expensive than GPT-5.5 Instant.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Only GPT-5.5 Instant specifies input context (400,000 tokens). Only GPT-5.5 Instant specifies output context (128,000 tokens).
Input capabilities
Documented input modalities across available providers
Both GPT-5.5 Instant and GPT-6 Rosalind support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
GPT-5.5 Instant
GPT-6 Rosalind
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
GPT-5.5 Instant was released on 2026-05-05, while GPT-6 Rosalind was released on 2026-10-30.
GPT-6 Rosalind is 6 months newer than GPT-5.5 Instant.
May 5, 2026
6 months ago
Oct 30, 2026
5 days ago
5mo newerKnowledge Cutoff
When training data ends
GPT-5.5 Instant has a documented knowledge cutoff of 2025-08-31, while GPT-6 Rosalind's cutoff date is not specified.
We can confirm GPT-5.5 Instant's training data extends to 2025-08-31, but cannot make a direct comparison without GPT-6 Rosalind's cutoff date.
Aug 2025
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Provider Availability
GPT-5.5 Instant is available from OpenAI. GPT-6 Rosalind is available from OpenAI.
GPT-5.5 Instant
GPT-6 Rosalind
Outputs Comparison
Judge for yourself.
Run your own prompts against GPT-5.5 Instant and GPT-6 Rosalind side-by-side, then vote on the output you prefer.
FAQ
Common questions about GPT-5.5 Instant vs GPT-6 Rosalind.