While Submagic makes adding subtitles in 100+ languages easy, it yet adds up when you count 100s, if not 1000s of videos. Enter the subtitles API. If you just want to sign up for free and give it shot - go ahead.
Otherwise, read a bit more, then sign up. Ready when you are. This is our API page.
We’ve spoken to 100s of creators, agency owners, and large businesses. No one wants to manually generate subtitle files anymore.
Imagine this scenario. You’ve got videos to edit, campaigns to ship, and content to launch in five different languages by, like, yesterday. Whether marketer automating post-production or a developer looking to streamline workflows for your video product, manually adding captions is a painful bottleneck.
That’s where Submagic’s subtitle API steps in. Fast. Accurate. JSON out, VTT/SRT in. We make it easy to transcribe, translate, and subtitle videos using a single REST API call, or no code at all if that’s your flavor.
Here’s the three main takeaways we’ll dive into.
- Automate subtitles fast – Transcribe, translate, and generate SRT/VTT in seconds with a single API call.
- Dev-friendly, no-code ready – Works with JSON, curl, Python, or no-code tools like Zapier.
- One API, full workflow – Handles audio, video, YouTube links, styling, metadata, and more.
Ready for the fun part? Let me show you how it works and where it fits in real-world workflows.
Why automate subtitles in the first place?
Two reasons: reach and speed.
Subtitles increase watch time, engagement, and accessibility. But more importantly, if you’re localizing content or handling hundreds of videos a week (hey, agencies, we see you), then a subtitle automation pipeline is the only sane path forward.
Manual transcription and subtitle generation adds up fast, 10 minutes here, 30 minutes there. Multiply that by 40 videos, across five platforms, in three languages. That’s a full-time job.
Submagic’s subtitle API turns it into a 3-second task.
Here’s what the Submagic API does
With a simple POST request, you can:
- Transcribe video and audio files into subtitle-ready text
- Generate subtitle files (SRT, VTT, and more)
- Translate subtitles into over 100+ different languages
- Add timestamps, line breaks, speaker labels, and other metadata
- Download subtitle files or inject as closed captions (no watermark)
- Use optional parameters for overlay styling, burned-in subtitles, or JSON output to build your own player logic
And it works with just about anything: .mp4, .mov, .mp3, .wav, .mkv, .avi, YouTube links, local video files, you name it.
Since you are reading about subtitle automation, you should check out the best tools for the job. See the best Subtitle generator APIs tier list.
Use cases for the subtitle API
We’ve seen it used in wild and wonderful ways, but here are some common patterns:
1. In-product transcription
You're building a video editor, podcast platform, or LMS. You want users to upload video/audio and instantly get captions.
How it works:
- User uploads a video
- You send it to our
transcribe endpoint with an API key - We return a clean subtitle file (SRT or VTT) with timestamps and optional styling
- You overlay or download the subtitle
2. Localization workflows
Marketing teams running campaigns across regions use our API to instantly translate subtitles into French, Spanish, Japanese, even Swahili. Combine that with your subtitle generator and boom: you're now global.
3. Dev automation & batch processing
Using curl, Python, Java, or PHP? You can hit our REST API to process batches of audio files and get clean captions back in minutes.
Great for:
- Agencies uploading content for 10+ clients
- Batch-editing YouTube videos for social repurposing
- Building open-source tools with subtitle overlay
Check our docs and GitHub templates for quick copy-paste examples.
Developers, here’s what you’ll love
Submagic’s API is ridiculously straightforward, yet we documented it.
- Authentication: Just add your API key in the headers.
- Content-type:
application/json or multipart/form-data. - Output formats: JSON, SRT, VTT
- Languages: 100+ supported
- SDKs: Python, Node, PHP, Java, Android templates
- Metadata: Full timestamps, durations, line positioning, speaker labels
- No-code: Zapier, Make, and other integrations available
- Watermark: None. It’s your subtitle. Your overlay.
Here’s a basic curl example to generate subtitles from a video file:
curl -X POST https://api.submagic.co/v1/subtitles \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: multipart/form-data" \
-F "file=@/path/to/video.mp4"
And boom, you get back your SRT or JSON with timestamps, in the language of your choice.
Need closed captions burned into the video itself? Add overlay=true to the request body.
Want to subtitle your YouTube videos?
We support that, too. Pass a public YouTube URL into the API and get back translated captions or auto-subtitles in VTT/SRT.
Perfect for:
- Creators who want multilingual support without editing in YouTube Studio
- Agencies batch-processing channels for clients
- Social media teams scaling Shorts, Reels, and TikToks with subtitles built in
Skip the code entirely with no-code integrations
Not a developer? No problem.
You can still generate subtitles without touching JSON or authentication headers. Our no-code builder lets you upload, transcribe, translate, and style subtitles in seconds. It’s all drag, drop, and done, no Terminal required.
If subtitles are a regular part of your workflow, whether you’re a dev, editor, or content ops lead, you shouldn’t be doing them manually anymore.
The Submagic subtitle API gives you fast, accurate, multilingual subtitles in a format your pipeline already understands. Automate it. Style it. Ship it. In 3 clicks or less.
Need to test it? Grab a free API key, send a request, and see your transcript in action.
| Feature |
What it does |
transcribe endpoint |
Converts video/audio into clean, timestamped text |
| Subtitle formats |
SRT, VTT, JSON |
| Language support |
100+ different languages |
| Output options |
Overlay, metadata, speaker labels, styling |
| SDKs |
Python, Java, PHP, Android, curl, HTML templates |
| No-code support |
Zapier, Make, Submagic UI |
| Ideal for |
Video editors, devs, marketers, localization teams |
| Input types |
Audio files, video files, YouTube links |
| Authentication |
API key in headers |
| Docs |
Submagic API docs |
