Free online ULT to FLAC converter

Source format: ULT

ULT is a tracker music module format associated with UltraTracker, a DOS-era music tracker. It stores song data such as patterns, instruments, samples, and playback instructions rather than a finished audio stream. ULT files were used by tracker musicians and demoscene creators to compose compact, loopable music for games, demos, and personal projects.

Because ULT is a module format, it is not directly playable everywhere. To listen to it on modern devices or archive it in a more universal form, it is often converted to a standard audio file such as FLAC.

Target format: FLAC

FLAC stands for Free Lossless Audio Codec. It compresses audio without losing any information, so the decoded sound is identical to the original rendered audio. FLAC is widely supported by music players, media servers, and archival tools, making it a strong choice for preserving tracker music in a high-quality, future-friendly format.

Compared with uncompressed WAV, FLAC usually produces much smaller files while keeping full audio fidelity. It is commonly used for music archiving, library management, and high-quality playback.

How to convert ULT to FLAC

The key point is that ULT is not audio; it must first be rendered by a tracker player or converter, then saved as FLAC. The easiest method is to use a player or converter that can open ULT modules and export the rendered output.

1. Open the ULT file in a compatible tracker player or converter. Good desktop options include OpenMPT, XMPlay with the appropriate plugin support, or other module players that can load UltraTracker files.
2. Play the module once to confirm it loads correctly and sounds as expected. This is important because some ULT files rely on tracker-specific effects or sample behavior.
3. Use the program’s export or render function. In OpenMPT, for example, choose File → Export → Wave or a similar render option, then export the song to .wav.
4. After rendering to WAV, convert the WAV file to FLAC using a lossless audio encoder such as ffmpeg or flac. For example, with ffmpeg you can run ffmpeg -i input.wav output.flac.
5. If your tracker software can export directly to FLAC, choose that option and save the file as .flac without the intermediate WAV step.

If you prefer a simple browser-based workflow, you can convert the file on 101convert.com for free without installing any software, provided the site supports the specific ULT-to-FLAC conversion path.

Quality, compatibility, and limitations

Rendering quality matters because FLAC preserves whatever audio the tracker player produces. If the module is rendered with the wrong sample rate, interpolation setting, or effect handling, those issues will be permanently baked into the FLAC file.

Some ULT files may sound slightly different across players because tracker formats can depend on playback engine behavior. For best results, use a modern tracker that accurately supports UltraTracker modules and render at a standard sample rate such as 44.1 kHz or higher.

FLAC is excellent for preservation, but it is still an audio snapshot of the module, not the editable tracker project. Keep the original .ult file if you may want to edit or re-render it later.