# What are voice codecs (G.711, Opus)?

> A voice codec encodes analogue speech into digital packets for transport and decodes it back, trading bandwidth against audio quality. G.711 is the classic uncompressed toll-quality codec at ~64 kbit/s, ubiquitous and low-latency but bandwidth-heavy. Opus (RFC 6716) adapts its bitrate dynamically and is highly resilient to packet loss, making it the modern choice for VoIP and WebRTC. Transcoding between codecs on a call path costs quality and adds delay. See /answers/voip-quality, /answers/what-is-webrtc, and /products/voice.

- Canonical URL: https://www.broadnet.me/answers/what-is-voice-codec
- Language: en
- Last reviewed: 2026-07-22
- Publisher: BroadNet (https://www.broadnet.me)

## Related

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- [What determines VoIP call quality?](https://www.broadnet.me/answers/voip-quality)
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- [Voice](https://www.broadnet.me/products/voice)