When it comes to delivering crystal-clear audio over the internet, choosing the best voice codec for VoIP is crucial. Whether you’re building a business phone system, developing a VoIP app, or just want the best call quality, the right codec can make a world of difference. In this guide, we’ll break down the top VoIP codecs for 2025 based on audio quality, bandwidth efficiency, latency, and compatibility.

What Is a Codec in VoIP?

A codec (short for coder-decoder) compresses and decompresses audio data for transmission over IP networks. The right codec balances quality, bandwidth usage, and processing requirements to ensure reliable and clear voice communication.

1. Opus – The Gold Standard for VoIP Quality

Opus is widely regarded as the best voice codec for VoIP in 2025. It offers unmatched audio quality across a wide range of bitrates and conditions.

• Bitrate: 6–510 kbps (adaptive)
• Sampling Rate: 8 to 48 kHz (narrowband to fullband)
• Pros:
  • Exceptional voice quality at both low and high bitrates
  • Ultra-low latency (~5 ms)
  • Supports wideband, superwideband, and fullband audio
  • Open-source and royalty-free
• Used by: WebRTC, Discord, Zoom, WhatsApp

Why Choose Opus? Opus is ideal for both VoIP and real-time streaming. It’s versatile, resilient to network issues, and optimized for human speech and music alike.

2. G.722 – Reliable and Widely Supported

G.722 is a wideband codec commonly used in enterprise VoIP systems.

• Bitrate: 64 kbps
• Sampling Rate: 16 kHz
• Pros:
  • Higher clarity than legacy codecs like G.711
  • Low latency
  • Compatible with most IP phones and PBX systems
• Cons:
  • Consumes more bandwidth than modern codecs like Opus

Ideal For: Businesses using SIP trunks, IP PBXs, or desk phones.

3. EVS (Enhanced Voice Services) – Next-Gen Mobile Quality

EVS is a cutting-edge codec designed for mobile networks like VoLTE, delivering near-studio quality voice.

• Bitrate: 5.9–128 kbps
• Sampling Rate: 8 to 48 kHz
• Pros:
  • Exceptional audio quality and robustness
  • Superior performance in poor network conditions
• Cons:
  • Licensing costs
  • Not yet widely supported in consumer VoIP platforms

Best For: Mobile carriers and VoLTE implementations aiming for HD voice.

Honourable Mentions

G.711 (µ-law and A-law)

• Bitrate: 64 kbps
• Sampling Rate: 8 kHz
• Pros: Zero compression = low latency
• Cons: Narrowband quality only

SILK & iLBC

• SILK: Skype’s original codec, now part of Opus
• iLBC: Good for packet loss but outdated

Quick Comparison: Best VoIP Codecs in 2025

Final Thoughts

If you’re seeking the best audio quality for VoIP in 2025, Opus is your top choice for versatility, clarity, and bandwidth efficiency. For mobile and telecom-grade quality, EVS leads the way—if licensing isn’t an issue. Meanwhile, G.722 offers a solid middle ground for traditional business VoIP environments.

Choosing the right codec means better voice quality, happier users, and more reliable communication. Make sure to assess your bandwidth, device compatibility, and latency needs when selecting the best voice codec for your VoIP solution.