OPUS to FLAC Converter

OPUS to FLAC Converter

Opus is a lossy streaming codec built for voice and music at low bitrates; FLAC is a lossless archival codec that stores audio bit-for-bit. This converter decodes your Opus audio and re-encodes it as FLAC — useful when an editor, player, or hardware device only accepts lossless input. One thing to be clear about up front: converting Opus to FLAC does not restore quality. The detail Opus discarded during its original lossy encode is gone, and FLAC can only losslessly preserve whatever the Opus file already contains. You get a larger file that sounds identical to the source, not a better one.

OPUS Format at a Glance

FLAC Format at a Glance

Because Opus already throws data away and FLAC keeps everything, a FLAC made from Opus is typically several times larger than the Opus source while carrying no extra audible information. FLAC's advantage shows up only when your source is already lossless — it is the wrong tool for "upgrading" a lossy file, and the right tool for storing a master without further loss.

How to Convert OPUS to FLAC

1. Upload Your OPUS File: Drag and drop your .opus file onto the page or click "+ Add Files" to browse. You can queue several files to convert in one batch.
2. Set the Compression Level: Use the Compression level slider (1-12) to trade encoding speed for file size. Higher levels produce a smaller FLAC; the decoded audio is identical at every level because FLAC is lossless.
3. Adjust Audio Channel or Sample Rate (Optional): Leave Audio Channel and Audio Sample Rate on "Original" to preserve the source exactly, or override them if a target device needs a specific layout. The Trim control can cut the clip to a start/duration range.
4. Convert and Download: Click "Convert" and download your FLAC file. No sign-up, no watermark.

Files are uploaded over an encrypted connection, processed on our servers, and deleted automatically a few hours after conversion — never shared, never made public. Need the opposite direction to shrink a file back down for sharing? Use FLAC to Opus.

Frequently Asked Questions

Will converting Opus to FLAC improve the audio quality?

No. Opus is a lossy codec, so some audio information was permanently discarded when the file was first encoded. FLAC is lossless, which means it can store exactly what is in the Opus file — no more, no less. The FLAC output will sound the same as the Opus source, just in a larger, lossless container. To get genuinely higher quality you would need to start from a lossless or uncompressed master.

Why is my FLAC file so much larger than the Opus original?

Opus achieves small sizes by discarding inaudible (and some audible) data; a typical music Opus stream runs roughly 96-160 kbit/s. FLAC stores audio losslessly, so it encodes far more bits per second even when the underlying audio came from a lossy source. A multiple-times-larger output is expected and normal for this conversion — it reflects FLAC's lossless storage, not added quality.

Does the compression level change how the FLAC sounds?

No. FLAC is lossless at every compression level, so levels 1 through 12 all decode to bit-for-bit identical audio. The only difference is the tradeoff between output file size and encoding time: higher levels search harder for redundancy and produce a smaller file but take longer to encode. In our testing, raising the level on an already-lossy Opus source shaves only a little off the size, because lossy audio has less exploitable redundancy than a true lossless master.

Does FLAC keep the tags and album art from my Opus file?

FLAC supports rich metadata through VORBIS_COMMENT blocks for text tags (title, artist, album) and PICTURE blocks for embedded album art, mirroring the Vorbis Comment system Opus uses in its Ogg container. Common fields carry over during conversion. If a niche or non-standard tag matters to you, verify it in your tag editor after converting, since field mapping between containers is not always one-to-one.

Is the FLAC format still actively maintained?

Yes. FLAC has a long-stable bitstream and is developed by the Xiph.Org Foundation. In December 2024 the format was formally standardized as IETF RFC 9639, giving it a vendor-neutral written specification. It remains non-proprietary and unencumbered by patents, which is a large part of why it is the default lossless format for archival and audiophile use.

When should I convert Opus to FLAC instead of to MP3 or WAV?

Choose FLAC when a workflow, audio editor, or hardware player specifically requires a lossless input, or when you want a single archival copy that will not lose further quality if re-encoded later. If your goal is broad device compatibility or a smaller shareable file, Opus to MP3 is usually the better fit, since FLAC made from a lossy source is large without sounding better. WAV is worth picking only when an application demands uncompressed PCM specifically.

What sample rate and bit depth will the FLAC be?

Opus operates internally at 48 kHz, so decoding an Opus stream produces 48 kHz audio regardless of the sample rate the original was recorded at — the FLAC is typically written at 48 kHz unless you override the Audio Sample Rate control. This is normal and does not mean quality was added by upsampling; it simply reflects how the Opus decoder works. If a target device needs a specific rate, set it under Audio Sample Rate before converting rather than relying on a later resample.

Which players and devices can open a FLAC file?

FLAC plays natively on Windows 10 and 11, on Android (which decodes FLAC up to 24-bit/192 kHz), and in cross-platform players such as VLC and foobar2000. Apple is the notable gap: the Music app does not import FLAC because Apple ships its own ALAC lossless format instead, so on an iPhone or in iTunes you would play the file through VLC or convert it to ALAC first. That Apple limitation, not any flaw in the file, is the usual reason a FLAC "won't open."