1Upload the FLAC audio files whose level you want to change.
2Move the volume slider: above 100% makes the file louder, below 100% makes it quieter.
3Run it; the whole file is raised or lowered by the same amount, so a large boost can make loud passages clip.
4Download the adjusted FLAC file.
Adjust FLAC Volume FAQ
Anything specific to FLAC to know?
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Yes — FLAC decodes bit-identically to the source, so any number of edit-and-resave cycles cost you nothing in fidelity. Relevant if you plan to adjust the level more than once.
Can I adjust a whole batch to the same gain?
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Several files in one job need a paid plan. Free use is one file per conversion, one conversion an hour. On a paid plan you can add several files to one job, then download each result on its own or all of them in one ZIP.
How does Adjust FLAC Volume change the level?
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Concretely, the gain is applied to the PCM samples directly, so the change is exact and reversible; headroom is checked before writing so a boost clips nothing. You move the volume slider, where 100% leaves the level unchanged, and the change is applied evenly across the whole file.
Does Adjust FLAC Volume cost anything?
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No. Adjust FLAC Volume is free without an account, and nothing is added to the audio. The upload and the result are deleted automatically about 24 hours after the job, which leaves time to download the result.
What can I upload to Adjust FLAC Volume?
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WAV, FLAC and AIFF, at any bit depth and sample rate up to and including 24-bit/192 kHz. Lossy files work in the same batch if you are mixing sources.
Is there a file size limit on Adjust FLAC Volume?
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Yes: free accounts process audio up to 15 MB per file — for uncompressed PCM that is roughly twenty minutes of CD-quality stereo, so it is a real limit here in a way it is not for MP3. If you are over it, converting WAV to FLAC first is the free fix — it is lossless and roughly halves the size.
Are bit depth and sample rate preserved?
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Yes, unless you change them deliberately. A 24-bit/96 kHz source stays 24-bit/96 kHz — nothing is silently downsampled to 16/44.1, which is the failure mode that makes a master unusable.
Why does a MP3 site host Adjust FLAC Volume?
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MP3.to is built around the format that made portable audio ordinary: universally playable, small enough to ignore, and lossy in a way that only matters if you keep re-encoding it. Audio jobs cluster: the same person who needs a format changed usually needs the file cut, levelled or made smaller in the same sitting. Putting Adjust FLAC Volume behind the same upload, the same caps and the same account is what turns three tabs into one.
What should I do with the result once Adjust FLAC Volume is finished?
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The converter on this site moves audio between MP3, WAV, FLAC, M4A, OGG and Opus, so the output format is a decision you can leave until the end rather than commit to at the start. Doing that after Adjust FLAC Volume rather than before means the encode happens once, on the file you actually settled on, instead of twice.
Is Adjust FLAC Volume here the same tool the sibling sites run?
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The engines are shared — the same ffmpeg build, the same workers, the same limits. What a MP3 site adds is a point of view about bitrates, about what survives an encode and about when a lossless intermediate is worth the upload time. It also starts from one fact about the format this site is named after: MP3 frames are fixed-size blocks, so a cut lands on a frame boundary and gapless playback markers do not survive a re-encode.
Do I need an account, and does anything get kept?
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No account is needed. Uploads and results are kept for about 24 hours, which leaves time to download the result, and are then deleted automatically; nobody reads, lists or indexes them. Several files in one job need a paid plan.
