subtitld 26.10.18.124

A free and open source subtitle editor for Linux, Windows, macOS and Haiku.
Time subtitles on the waveform, transcribe and translate them with engines that can run on your own machine, and dub them with synthetic voices.

Install · Features · Add-ons · Formats · Run from source · Website · Discord

Features

⏱️ Timing on the waveform

• A timeline with the audio's waveform: drag a subtitle to move it, drag its edges to retime it.
• Snapping to the neighbouring subtitles and to a grid of frames or seconds, with zoom for fine work.
• A vertical timeline beside the list, for working down the subtitles.
• Set a subtitle's start or end to the playhead, slice it in two, merge it with its neighbour, nudge it by a step.
• A quality check against reading speed (characters per second, words per minute), duration, line count and line length, with the usual limits as defaults.

🎬 Video and audio

• The video with the current subtitle drawn over it, as it will be seen, with safe-area guides.
• Playback speed, looping and frame stepping.
• A mixer for the video's sound and the dubs, with EQ, compressor and gate per track.
• 4K and 8K videos get a lighter proxy to edit with, made on the GPU where there is one.

🗣️ Speakers

• Name the speakers and give them a face from the video; each one gets a colour, and a lane of their own on the timeline if you like.
• See how long each one speaks.

🤖 Transcription, translation and dubbing

• Transcribe the video's speech into timed subtitles: all of it, a range, or the selection. Or speak into the microphone and watch it become subtitles.
• Translate the subtitles, keeping each language's translation alongside the original.
• Dub: speak every subtitle with a synthetic voice, one voice per speaker. Dubs can be fitted to each subtitle's duration, and voices that clone take their sample from the video. Or record your own voice instead.
• Export the dub as WAV, FLAC or MP3: the whole mix, a track per speaker, the clips, or the background or the voices alone.
• Transcription and translation engines, and more voices, are add-ons, many of them fully offline. Two online voices (Edge and Google) come built in.

✍️ Editing

• Undo, find and replace (with regular expressions), autosave and backups.
• A plain-text view to edit all the subtitles as one document, as SRT, Markdown or JSON.
• Keyboard shortcuts, which you can change.
• Recent files reopen where you left off.
• Import a transcript from a text or Word file, sliced into subtitles.

🌐 subtitld.cc

subtitld.cc is Subtitld's community hub. When a video opens, Subtitld can look up subtitles made for that exact file (it sends a fingerprint, never the video or its name). You can also search, rate and open subtitles there, and publish your own, all from inside the app.

Speakers, each on a track of their own	The vertical timeline

_{Screenshots: Tears of Steel, © Blender Foundation, CC BY 3.0.}

Install

Linux	Arch Linux: subtitld on the AUR · Any distribution: the AppImage from the latest release
Windows	Or the installer, or the portable version, from the latest release
macOS	With Python, from PyPI
Haiku	Coming to HaikuPorts; the recipes are in packaging/haiku

From PyPI

On any system with Python 3.10 to 3.14 and FFmpeg on the PATH:

pip install subtitld
subtitld

On Linux, the audio also needs PortAudio (libportaudio2 on Debian and Ubuntu).

Add-ons

Speech recognition, translation, more voices and audio separation come as add-ons, installed from inside Subtitld (Add-ons in the global settings). Each one brings its own models, so the app stays small and you only download what you use.

	Add-ons
Speech to text	whisper.cpp (offline) · Vosk (offline) · RealtimeSTT (offline, as you speak) · AssemblyAI (cloud)
Translation	Offline translation (OPUS-MT models, no API key)
Voices	Piper · Kokoro · Supertonic · sanoTTS · Parler-TTS · with voice cloning: Qwen3-TTS, Coqui XTTS and F5-TTS
Audio	Audio separator: split the voices from the music and effects

The list Subtitld shows comes from Subtitld/addons-catalog. Some models are for non-commercial use only; each add-on's page says which.

Formats

Open and save	SubRip (.srt) · WebVTT (.vtt) · TTML (.ttml) · DFXP (.dfxp) · SAMI (.smi, .sami) · Scenarist (.scc) · JSON · Universal Subtitle Format (.usf)
Open	SubStation Alpha (.ass, .ssa; the text, not the styles) · MicroDVD (.sub) · iTunes Timed Text (.itt) · XML
Projects	.usfx: the subtitles bundled with the speakers' faces and dubs, and, if you choose, the waveform and the video
Transcripts	Import from .txt, .docx and .srt
Video	MP4, MKV, MOV, WebM, MPEG, Ogg and M4V, through FFmpeg
Dub	WAV, FLAC, MP3

Run from source

You need Python 3.10 to 3.14, FFmpeg, and on Linux PortAudio.

git clone https://github.com/Subtitld/subtitld.git
cd subtitld
python3 -m venv .venv
.venv/bin/pip install -e .
.venv/bin/subtitld

Tests

Each test is a script that runs Qt off-screen, with its own scratch settings:

for t in tests/test_*.py; do .venv/bin/python "$t" || echo "FAILED: $t"; done

Packaging

Every package is built by CI from this repository: build.yml builds them all without publishing, and release.yml publishes them on a version tag.

Package	Where it's defined
Wheel (PyPI)	pyproject.toml
AppImage	AppImageBuilder.yml
Snap	snap/snapcraft.yaml
Flatpak	flatpak/
AUR	packaging/aur/
Windows: installer, portable, Microsoft Store	nsis-installer.nsi · packaging/msix/ · subtitld-windows.spec
macOS app	subtitld-macos.spec
Haiku	packaging/haiku/

The icons, installer pictures and this page's banner are drawn from two SVGs by packaging/branding/render-icons.py.

Contributing

Bugs and ideas go in the issues; pull requests are welcome. For questions, help, or just to talk subtitles, join us on Discord. If Subtitld is useful to you, you can also support its development.

License

Subtitld is free software, released under the GNU General Public License v3.0.