Free online SRT to OGG converter

When a player or workflow needs spoken audio rather than subtitle captions, an SRT file must be rendered as speech and saved in an audio format such as OGG. This is a text-to-speech conversion, not a direct change of file extension.

What the SRT format is

SRT is a plain-text subtitle format containing numbered caption entries, start and end timestamps, and the words shown on screen. Video editors, subtitle editors, and media players create or use SRT files; the format is common when downloading captions separately from a video.

What the OGG format is

OGG is a container for audio streams, commonly encoded with Vorbis or Opus. It is used for audio playback and distribution; an OGG file can hold synthesized speech, but it does not retain subtitle entries as captions.

How to convert SRT to OGG

Because SRT contains words rather than recorded speech, conversion requires a text-to-speech voice. The resulting OGG contains spoken audio, not the original timed captions.

Online on 101convert.com

1. Open the SRT-to-OGG converter on 101convert.com and upload the subtitle file. Multiple files can be added for batch conversion; the per-file size limit is shown on the page.
2. Before converting, set the voice language, reading speed, and subtitle timing as needed.
3. Start the conversion and download the OGG file when it is ready.

Offline with desktop software

For local processing, use the free eSpeak NG text-to-speech engine and FFmpeg. Install both for your operating system (Windows, macOS, or Linux), then use Python to remove SRT sequence numbers and timestamps before synthesis.

import re
from pathlib import Path

s = Path("captions.srt").read_text(encoding="utf-8-sig")
s = re.sub(r"(?m)^\s*\d+\s*$", "", s)
s = re.sub(r"(?m)^\d{2}:\d{2}:\d{2}[,.]\d{3}\s+-->.*$", "", s)
Path("captions.txt").write_text(s, encoding="utf-8")

Run the script in the folder containing captions.srt, then synthesize and encode the narration:

espeak-ng -f captions.txt -w narration.wav
ffmpeg -i narration.wav -c:a libvorbis -q:a 5 narration.ogg

This local method speaks captions sequentially and does not preserve their original start times or pauses. Use a timing-aware workflow if the spoken audio must stay synchronized with video; check the resulting voice pronunciation and OGG playback in the target player.