FLAC to Opus Converter
Initializing... drag & drop files here
Supports: FLAC
Advanced Options - Our defaults are optimized for the best results. We recommend you keeping the defaults unless you have a specific need.
Reset to defaults
Need help?How to Convert FLAC to Opus
- Upload Your FLAC File — Click "Choose Files" or drag and drop your FLAC audio file. Only .flac files are accepted.
- Set Audio Quality — Under File Compression, choose from: Quality Preset (Highest through Lowest), File Size Percentage (1-100% slider), Specific File Size (MB/KB), Custom Bitrate (enter any value in kbps), Constant Bitrate (32-384 kbps presets), or Variable Bitrate.
- Adjust Audio Settings (Optional) — Under Audio Codec, the default is Opus. Set Audio Channel to Original, Mono, or Stereo. Change Audio Sample Rate from 8000 Hz through 48000 Hz.
- Trim (Optional) — Under Trim, set a Start Time and Duration in seconds or HH:MM:SS.sss format.
- Convert & Download — Click "Convert" and download your Opus file.
Why Convert FLAC to Opus?
FLAC is a lossless audio format — perfect quality but large files (typically 30-50 MB per song). Opus is a modern lossy codec that delivers near-transparent quality at a fraction of the size. Converting FLAC to Opus is ideal for creating a portable music library that fits on phones and portable players, streaming audio over bandwidth-limited connections, sharing music files via messaging or email with minimal size, and preparing audio for web applications and HTML5 <audio> elements.
In testing, a 50 MB FLAC file converts to roughly 8-10 MB as Opus while remaining virtually indistinguishable from the original to most listeners.
FLAC vs Opus Comparison
| Feature | FLAC | Opus |
|---|---|---|
| Compression | Lossless | Lossy |
| File size (5 min song) | 30-50 MB | 5-10 MB |
| Quality | Perfect (bit-identical) | Near-transparent |
| Bitrate | ~800-1400 kbps | 64-256 kbps |
| License | Open-source | Royalty-free |
| Player support | Most modern players | Chrome, Firefox, VLC, Android 5+ |
| Best for | Archival, audiophile | Streaming, mobile, web |
Recommended Opus Bitrates for FLAC Sources
| Bitrate | Quality | File Size Reduction |
|---|---|---|
| 96 kbps | Transparent for most | ~90% smaller than FLAC |
| 128 kbps | Indistinguishable | ~85% smaller |
| 160 kbps | Overkill for most content | ~80% smaller |
| 192 kbps | Maximum quality | ~75% smaller |
What bitrate should I use for music from FLAC?
128 kbps Opus is virtually indistinguishable from the FLAC source for most listeners. Use 96 kbps for a good balance of quality and size. Audiophiles may prefer 160-192 kbps for critical listening, though the difference is rarely audible.
Will I lose quality converting FLAC to Opus?
Technically yes — Opus is lossy. However, at 128 kbps, Opus is transparent to most listeners in blind tests. The quality loss is far less than converting to MP3 at the same bitrate. Starting from a lossless FLAC source ensures the best possible Opus output.
Why choose Opus over MP3?
Opus at 96 kbps sounds comparable to MP3 at 192 kbps — roughly half the file size for the same perceived quality. Opus also handles both speech and music better than MP3.
Can I trim the audio during conversion?
Yes. Under Trim, switch to "Trim" and enter a Start Time and Duration. This extracts a specific segment.
What players support Opus?
VLC, foobar2000, Chrome, Firefox, Edge, Safari 17+, Android 5.0+, iOS 17+, and most modern media players. For legacy device compatibility, consider FLAC to MP3 instead.