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AI model reference · 2026

GPT-5.5

OpenAI: GPT-5.5 logoOpenAIModel details, evidence, and API facts

GPT-5.5 is OpenAI’s frontier model designed for complex professional workloads, building on GPT-5.4 with stronger reasoning, higher reliability, and improved token efficiency on hard tasks.

Text generation
Image input
Reasoning
Provider endpoint accepts tool parameters
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Context window
1,050,000 tokens
Maximum output
128,000 tokens
Base provider API input
$5.00 / 1M tokens
Starting provider API rate; context tiers apply
Published evidence
4 benchmarks, 1 Arena result

Overview

About GPT-5.5

A concise catalog overview. Technical limits and published evaluation evidence are listed separately below.

GPT-5.5 is OpenAI’s frontier model designed for complex professional workloads, building on GPT-5.4 with stronger reasoning, higher reliability, and improved token efficiency on hard tasks.

text
multimodal
reasoning

Published evaluations

Benchmark results

Only results mapped to this exact model and backed by a named source appear here. Different evaluation protocols are not treated as interchangeable.

Source-backed benchmark results for GPT-5.5
BenchmarkScoreEvaluation detailsSource
AutomationBench-AAA 657-task benchmark of multi-step work across simulated SaaS applications in six business domains. The Artificial Analysis protocol reports a guardrail-aware score and is distinct from both the public Zapier split and the unrelated dynamic AutoBench framework.42.1%Guardrail-aware scoreVersion: AutomationBench-AA 2026 · Split: 657 tasks across Finance, HR, Marketing, Operations, Sales, and Support · Harness: Artificial Analysis independent implementation · Attempts: One evaluated run per task · Tools: REST APIs for simulated SaaS applications · Evaluator: Programmatic end-state grader with guardrail checks · Reasoning effort: xhighMethodology Artificial AnalysisIndependently reproduced
DeepSWE 1.1A long-horizon software-engineering benchmark with 113 original tasks graded by hand-written tests.67.0%±6Pass@1Version: DeepSWE 1.1 · Split: 113 tasks across 91 repositories · Harness: mini-swe-agent · Reasoning effort: xhighProtocol note: All models use the same harness. Cost, output-token, and step counts are retained per result as protocol context.; Confidence interval: ±6Methodology DataCurveBenchmark owner
Terminal-Bench 2.1Version 2.1 of the benchmark for completing realistic tasks in terminal environments. Harness, resource limits, and attempt count are part of the protocol.83.1%±1.1Mean task successVersion: Terminal-Bench 2.1, Harbor dataset revision 6 · Split: 89 revised tasks · Harness: Codex · Attempts: Five attempts per task · Reasoning effort: xhighProtocol note: Every result retains its agent. Rows with different agents are not model-only comparisons.; Agent: Codex; Run date: 2026-05-01; Confidence interval: ±1.1Methodology Terminal-BenchBenchmark owner
LiveBenchA contamination-resistant benchmark refreshed on a fixed release cadence. Scores from different LiveBench releases must never be compared as the same protocol.80.2%Mean of category averagesVersion: LiveBench 2026-06-25 · Split: 2026-06-25 release, 23 tasks across seven categories · Reasoning effort: xhighProtocol note: Overall is the mean of category averages. This protocol is not comparable with the 2026-01-08 release.Methodology LiveBenchBenchmark owner

Human preference

Arena results

Arena scores come from blind human preference votes. They are reported separately from task benchmarks and are not used as substitutes for missing benchmark results.

Arena results for GPT-5.5
CategoryScoreRankVotesStatus
Arena TextBlind human preference score for text responses.1,477±4#3070,781Published

Technical reference

Specifications and API facts

Technical limits and reference provider prices come from the current catalog unless a reviewed external source is listed. Missing values stay marked as unavailable.

Model
Provider
OpenAI
Release date
Not available in reviewed sources
Catalog added
Apr 24, 2026
Context window
1,050,000 tokens
Maximum output
128,000 tokens
Knowledge cutoff
2025-12-01
License
Not available in reviewed sources
Capabilities and API
Input types
File, Image, Text
Output types
Text
Reasoning
Supported
Provider endpoint tool parameters
Accepts tool parameters
Base provider API input
$5.00 / 1M tokens
Base provider cached input
$0.50 / 1M tokens
Base provider API output
$30 / 1M tokens
Provider tier at ≥ 272,000 prompt tokens
Input $10 / 1M tokensOutput $45 / 1M tokensCached input $1.00 / 1M tokens

Provider token rates are context-dependent. The base rates apply below the listed prompt thresholds; the matching tier applies at or above each threshold.

These are reference provider API rates, not Writingmate checkout charges. Access in Writingmate follows the allowances of your Writingmate plan.

Provenance

Sources and update status

Source links are attached to the facts and evaluations they support. Catalog-only values are not presented as independently verified claims.

Evidence last updated Oct 5, 2026.

Catalog record updated Apr 24, 2026.

Catalog-added dates describe when a model entered the catalog, not necessarily its public release date.

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