25 KB FLAC sample

A FLAC file of exactly 25,600 bytes. It is a valid Free Lossless Audio Codec file, generated by this site. Compare its checksum and test it with the parser used by your application. Use it wherever you need a 25 KB sample, test or dummy FLAC file.

sample-flac-25kb.flac

25 KB25,600 bytes

Download 25 KB FLAC

Created in your browser in a few seconds, then checked against the SHA-256 checksum. The file is not uploaded anywhere. No sign-up.

Type: audio/flac
SHA-256: 2e57550b3c15431a1b2b58159c02a0829f892fe825f032a6d5b5c44dd59ae7d2
Delivery: Created in your browser from static generator assets (how it works).

What is in this file

2 FLAC frames (0.1 s) of a synthesised musical phrase that repeats every eight seconds. The samples are stored verbatim, so the audio decodes bit for bit to the matching WAV data. 0 bytes of a standard PADDING metadata block bring the file to the exact size.

Duration	0.1 s
Sample rate	44,100 Hz
Channels	2 (stereo)
Bit depth	16-bit
Block size	4,096 samples
Encoding	Verbatim subframes (lossless, not compressed)
Tags	Vorbis comment (title, artist, album)

First bytes of the file

The first 64 bytes of sample-flac-25kb.flac as a hex dump: offset, bytes, then the same bytes as text. The FLAC signature is 66 4C 61 43.

00000000  66 4c 61 43 00 00 00 22  10 00 10 00 00 00 00 00 |fLaC..."........|
00000010  00 00 0a c4 42 f0 00 00  18 d0 c1 34 3c 1f df 9f |....B......4<...|
00000020  f7 4e 2a d4 53 e3 0e 06  3d f0 04 00 00 78 19 00 |.N*.S...=....x..|
00000030  00 00 53 61 6d 70 6c 65  54 65 73 74 46 69 6c 65 |..SampleTestFile|

Preview

Creates the file in your browser and shows it here.

Where 25 KB matters

A 25,600-byte file: the size of a small web image or a short document. These are the default limits a file of this size is useful for testing:

System	Limit	Note
TCP initial congestion window	About 14.6 KB (10 segments)	25 KB needs at least two flights of packets on a new connection.
Base64 encoding	Adds 33 percent	A 25 KB file becomes about 34 KB inside JSON or an email.

All 25 KB sample files

Use this file for

Checking email size handling
Checking transcoding to MP3, AAC or Opus
Verifying duration and tag reading

Testing notes for FLAC

Cover art lives in the metadata, so a three-minute song can carry several megabytes before its first audio frame.
Some tagging tools put an ID3 tag in front of the stream. The signature then no longer sits at byte 0, and a strict parser rejects a file that most players accept.

FLAC format reference

Technical details

File name	sample-flac-25kb.flac
Format	FLAC (Free Lossless Audio Codec)
Extension	.flac
MIME type	audio/flac
Size	25,600 bytes (25 KB)
Kind	Binary
Signature	66 4C 61 43
SHA-256	2e57550b3c15431a1b2b58159c02a0829f892fe825f032a6d5b5c44dd59ae7d2
Created	2026-10-23
Validation	See the listed size and SHA-256. Small downloads are checked in the browser; verify streamed downloads manually. A hash match does not prove parser compatibility.
Preview	Available on this page
Source	Generated in your browser by this site's generator; not copied from elsewhere
Licence	Free to use, modify and redistribute (terms)
Category	Audio

Check the stated structure and checksum against your application requirements. As with any download, scan the file with your own security tools before opening it. How files are made and checked

Verify your copy

This file is created in your browser, so it has no direct URL for curl or wget. The generator is designed to produce reproducible bytes. After saving, compare the checksum with the SHA-256 value above.

sha256sum sample-flac-25kb.flac     # Linux
shasum -a 256 sample-flac-25kb.flac # macOS

On Windows, run Get-FileHash sample-flac-25kb.flac -Algorithm SHA256 in PowerShell. For scripts and pipelines, save the file once and keep your own copy.

Related files

Questions about this file

Is this file exactly 25 KB?: Yes. It is 25,600 bytes, which is 25 KB in the binary units that operating systems and server limits use (1 KB = 1,024 bytes).
What is inside the 25 KB FLAC file?: 2 FLAC frames (0.1 s) of a synthesised musical phrase that repeats every eight seconds. The samples are stored verbatim, so the audio decodes bit for bit to the matching WAV data. 0 bytes of a standard PADDING metadata block bring the file to the exact size.
What audio is on the FLAC samples?: A short synthesised musical phrase that repeats, as 16-bit stereo at 44,100 Hz. It was generated by code for this site and is free of any music copyright.

Download