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AssemblyAI: Universal-3.5 Pro

Source description (English)

Universal-3.5 Pro is AssemblyAI's speech-to-text model served through its Sync API, returning a complete transcript with word-level timestamps in a single synchronous response for audio clips up to 120 seconds....

Overview

Model specifications

Context
Not provided
Maximum output
Not provided
Architecture
audio->transcription
Tokenizer
Other
Knowledge cutoff
Not provided
Moderated
No
OPENROUTER

Complete pricing

Synchronized OpenRouter rates. Token prices are shown per one million tokens.

Audio seconds
$0.000063
per second
Audio Seconds (Prompted)
$0.000069
per second
API

Quick start

Set OPENROUTER_API_KEY locally. Python requires requests; JavaScript runs in Node.js. Keep the key on the server.

API documentation

curl --fail-with-body https://openrouter.ai/api/v1/audio/transcriptions \
  -H "Authorization: Bearer $OPENROUTER_API_KEY" \
  -F 'model=assemblyai/universal-3-5-pro' \
  -F 'file=@audio.wav'
Capabilities

InputOutput

Input
audio
Output
transcription
API

Supported API parameters

Available providers

1 Provider

Checked: September 23, 2026

Live providers on OpenRouter

Provider availability, latency, throughput and routing can change continuously. Open the source page for current operational data.

OpenRouter

AssemblyAI

Not provided
Context
Not provided
Maximum output
Not provided