About OPUS Format

What is OPUS?

Opus is a modern, royalty‑free audio codec standardized by the IETF and designed for interactive speech, music streaming, and general‑purpose audio over the internet. It combines technology from the SILK (Skype) and CELT codecs into a single, highly flexible format.

Opus is usually stored in an Ogg container using the .opus file extension and is known for excellent quality at low bit rates, very low latency, and rapid adaptability to changing network conditions.

Technical Specifications

File Extension

.opus

MIME Type

audio/opus

Compression

Lossy (hybrid linear prediction and transform coding)

Bit Rates

From about 6 kbps up to 510 kbps per stream

Sample Rates

Internally 48 kHz (supports input from 8–48 kHz)

Channels

Mono, Stereo, up to multichannel configurations

Max Audio Channels

Up to 255 channels (specification limit)

Developed By

IETF with contributions from Xiph.Org, Mozilla, Microsoft, Skype and others

Key Features & Advantages

✅

Wide Bitrate Range: Works well from very low speech bit rates to transparent music quality at higher rates.

✅

Low Latency: Supports frame sizes as small as 2.5 ms, making it ideal for real‑time communication.

✅

Network Adaptation: Designed to adapt quickly to changing network conditions in VoIP and streaming.

✅

Excellent Quality at Low Bit Rates: Often outperforms older codecs like MP3, AAC, and Vorbis at comparable bit rates.

✅

Open & Royalty‑Free: Standardized by the IETF with a royalty‑free license, widely implemented in open‑source software.

✅

Versatile Use Cases: Suitable for voice chat, music streaming, podcasts, conferencing, and more.

Understanding OPUS Quality Levels

Bit Rate

Quality Level

Use Case

File Size (3 min)

16 kbps

Low / Speech

Voice calls over constrained networks

~360 KB

32 kbps

Good Speech

VoIP, conferencing, gaming voice chat

~720 KB

64 kbps

Acceptable Music

Background music, low‑bandwidth streams

~1.5 MB

96 kbps

High Quality ⭐

General music listening and streaming

~2.2 MB

128–160 kbps

Very High

Transparent music quality for most listeners

~3–3.8 MB

Common Use Cases

🎮

Gaming Voice Chat

Used in many modern games and communication platforms for low‑latency speech.

📞

VoIP & Conferencing

Widely used in web conferencing and calling solutions.

🎧

Music Streaming

Adopted by some services and radio stations for efficient streaming.

🌐

WebRTC

Mandatory audio codec in WebRTC, powering in‑browser real‑time communication.

🎙️

Podcasts & Live Shows

Suitable for live streaming spoken‑word and music content over the internet.

📱

Mobile Apps

Used in apps that need robust audio over varying network conditions.

Brief History

2009–2010

Development of CELT and SILK codecs that later merge into Opus.

2012

Opus standardized by the IETF as RFC 6716.

2010s

Rapid adoption in WebRTC, VoIP, and open‑source media players.

Present

Recognized as one of the most versatile and efficient audio codecs for internet applications.

Free OPUS Converter

Convert OPUS to Other Formats

Key Features of our Audio Converter

Lightning Fast Processing

Complete Privacy

No Size Restrictions

Advanced Settings

Multi-File Support

Absolutely Free

Supported Audio Formats

Lossless Quality Formats

Compressed Formats

Specialized Formats

How It Works

Upload File

Choose Format

Convert

Download Result