🔒 Your files stay on your device — core audio processing runs locally. Privacy details →
Find a toolCtrl K
🖼️
Free · In-browser · No upload

FLAC Cover Art Editor.

Add or change one JPEG or PNG front cover in a single FLAC or 2–50 files at once — locally, without re-encoding audio.

Before-and-after illustration of FLAC Cover Art: FLAC and image becomes Artwork-ready FLAC through Embed or extract art.
Before → process → afterSee the signal story, then hear it in the workspace.

FILE STRUCTURE MAP

FLAC Artwork Panel

Follow audio, metadata and delivery as separate layers. Container work is easier to trust when decoded audio, editable fields and the final export are shown as distinct stages with explicit preservation limits.

Before-and-after illustration of FLAC Cover Art: FLAC and image becomes Artwork-ready FLAC through Embed or extract art.
FLAC and imageEmbed or extract artArtwork-ready FLAC
A file pipeline: source bytes and decoded content pass through explicit structure rules before a new, inspectable delivery is written.
Open the full signal breakdownBest source, processing logic, limits and three-pass listening check
  1. FLAC and image

    Start with the right material

    Adding one JPEG or PNG front cover across a FLAC delivery without transcoding the music.

  2. Embed or extract art

    Understand the transformation

    The page replaces only type-3 front-cover PICTURE blocks, processes a batch sequentially, preserves every other block and audio byte, then builds a STORE ZIP with unique names and a versioned manifest.

  3. Artwork-ready FLAC

    Verify the usable result

    One edited FLAC, an extracted image, or one ZIP containing every accepted FLAC plus a machine-readable manifest.

Picture block

Where this workflow stops

Single-file input is capped at 48 MiB on mobile or 128 MiB on desktop. Batch input is capped at 64 MiB or 160 MiB respectively, with the same per-file limits and separate peak-memory guards; malformed files are rejected and each FLAC metadata block must fit the 16 MiB format limit.

THREE-PASS CHECK

Make the final decision by ear

  • Keep the untouched original until the exported file is verified.
  • Confirm sample rate, channels, duration and metadata independently.
  • Test the delivery in the application or device that will consume it.
Input
One FLAC, or a batch of 2–50 valid .flac files, plus one decodable JPEG or PNG cover.
Batch output
A STORE ZIP with uniquely named FLAC files and flac-cover-art-batch-manifest.json.
Preservation
Non-front artwork, other metadata-block payloads and encoded audio bytes are copied byte-for-byte.

How to add one cover to multiple FLAC files

  1. Choose Batch add/change cover and select 2–50 .flac files. The browser scans each metadata chain locally.
  2. Review the per-file statuses. Skip rejected or malformed rows before export.
  3. Choose one JPEG or PNG. It will replace or fill the type-3 front-cover slot in every accepted FLAC.
  4. Download the stored ZIP with uniquely named FLAC outputs and flac-cover-art-batch-manifest.json.

How it works: the editor validates each FLAC metadata chain, replaces only valid PICTURE blocks whose picture type is 3, keeps all other metadata payloads in source order and appends the original encoded audio payload unchanged. Multiple old front covers become one selected front cover.

Honest limits: single-file mode accepts up to 48 MiB on mobile or 128 MiB on desktop. Batch mode accepts 2–50 files, up to 64 MiB total input on mobile or 160 MiB on desktop, with the same per-file limits and a separate conservative 256 MiB / 512 MiB peak-memory preflight. The complete PICTURE block must be smaller than 16 MiB. Malformed files are rejected rather than repaired.

FLAC Cover Art: quick answer and technical limits

Quick answer: A single-file and 2-to-50-file FLAC front-cover editor that preserves the encoded audio and unrelated metadata byte for byte.

Best for
Adding one JPEG or PNG front cover across a FLAC delivery without transcoding the music.
How it works
The page replaces only type-3 front-cover PICTURE blocks, processes a batch sequentially, preserves every other block and audio byte, then builds a STORE ZIP with unique names and a versioned manifest.
What you get
One edited FLAC, an extracted image, or one ZIP containing every accepted FLAC plus a machine-readable manifest.

Know before you use it: Single-file input is capped at 48 MiB on mobile or 128 MiB on desktop. Batch input is capped at 64 MiB or 160 MiB respectively, with the same per-file limits and separate peak-memory guards; malformed files are rejected and each FLAC metadata block must fit the 16 MiB format limit.

Public browser workflow evidence

Question: Can the tool add a front-cover picture while preserving the compressed FLAC audio payload byte for byte?

Observed result: The exported FLAC contained a type-3 front-cover picture and retained the original compressed audio payload byte for byte.

Evidence boundary: The fixture covers one valid FLAC structure and one front-cover replacement path, not every malformed or unusual metadata layout.

Network observation: No audio-payload or cross-origin requests were observed during this published workflow.

Open the public benchmark, method and fixture →

Privacy: Selected audio is processed in this browser and is not uploaded to AudioWrench. Normal page assets can still be requested as described in the privacy notice. Privacy details →

FAQ

How do I add the same cover to multiple FLAC files?
Choose Batch add/change cover, select 2–50 valid .flac files, choose one JPEG or PNG, remove any rejected rows, then download the ZIP. The same image is embedded as the type-3 front cover in every output.
Does changing FLAC cover art re-encode the audio?
No. FLAC stores artwork before the encoded audio stream. This tool rebuilds the metadata chain, then copies the original audio payload byte-for-byte without decoding or re-encoding it.
What image formats and batch sizes are supported?
Cover art must be a decodable JPEG or PNG whose complete FLAC PICTURE block is smaller than 16 MiB. Batch mode accepts 2–50 FLAC files and also enforces device-aware input, per-file and estimated peak-memory limits shown in the tool.
Will back-cover artwork and FLAC comments be preserved?
Yes. Replacement removes only valid type-3 front-cover PICTURE blocks. Back covers, artist images, other PICTURE roles, Vorbis comments, unknown metadata-block payloads and the encoded audio payload are copied byte-for-byte.
What is included in the batch ZIP?
The ZIP uses STORE method 0 and contains one uniquely named .flac output per accepted source plus flac-cover-art-batch-manifest.json. The manifest records the operation, cover properties, file mapping, preservation guarantees and the memory preflight.
Are my FLAC files or cover image uploaded?
No. Selected FLAC files and cover art are read in browser memory and are not uploaded to AudioWrench. Normal page assets can still be requested as described in the privacy notice.