GPT-5.5
StableOpenAI · Released 2026-04 · openai/gpt-5.5
Overview
Flagship general-purpose model from OpenAI with state-of-the-art reasoning, coding and agentic performance across enterprise workloads. GPT-5.5 supports up to 1.1M tokens of context, native vision input, and an extended reasoning mode. Served through the FirmLink unified API with OpenAI-compatible endpoints.
Function CallingJSON ModeStreamingReasoningTextVision
API example
Fully OpenAI-compatible — just change the model field.
curl https://api.firmlinktech.com/v1/chat/completions \
-H "Authorization: Bearer $FIRMLINK_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "openai/gpt-5.5",
"messages": [{"role": "user", "content": "Hello!"}]
}'Related models
OpenAI
GPT-6 Astra Pro
Function CallingJSON ModeStreamingVision
1.1M context
$10.00 / $50.00per 1M tok in / out
View details
OpenAI
GPT-6 Astra
Function CallingJSON ModeStreamingVision
1.1M context
$10.00 / $50.00per 1M tok in / out
View details
OpenAI
GPT-5.6 Terra Pro
Function CallingJSON ModeStreamingVision
1.1M context
$2.00 / $12.00per 1M tok in / out
View details
OpenAI
GPT-5.6 Terra
Function CallingJSON ModeStreamingVision
1.1M context
$2.00 / $12.00per 1M tok in / out
View details
GPT-5.5 is provided by OpenAI and served through the FirmLink gateway. Availability and limits follow the provider's terms.