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How to Add Subtitles to Videos Using FFMPEGAPI.net

June 2026 FFMPEG API Team

In the age of video content, adding subtitles to enhance accessibility and viewer engagement has become crucial. FFMPEGAPI.net offers a powerful hosted REST API that enables developers to effortlessly burn ASS subtitles into videos. This article will guide you through using the 'Add Subtitles' endpoint, showcasing how simple and effective it is for video automation, especially for AI agents.

Understanding the Add Subtitles Endpoint

The 'Add Subtitles' endpoint is a POST method that allows you to burn ASS subtitles into a video file. This process involves downloading the video and subtitle files from the provided URLs and merging them seamlessly.

With FFMPEGAPI.net, developers can integrate subtitle addition into their applications without the hassle of managing FFmpeg infrastructure or server setups.

  • Effortlessly add subtitles to any video.
  • No server management necessary; just use the API.
  • Ideal for automating video workflows, especially in AI applications.

API Request Details

To utilize the 'Add Subtitles' feature, you'll need to send a POST request to the /api/add_subtitles endpoint. Below are the parameters required for the request.

  • video_url (string, required): The URL of the video to which you want to add subtitles.
  • subtitle_url (string, required): The URL of the ASS/SSA subtitle file.
  • async (boolean, optional): If set to true, the API will return a job_id immediately and process the request in the background.

Example Usage with cURL

Here’s how you can use cURL to add subtitles to a video using the FFMPEGAPI.net API.

curl -X POST https://ffmpegapi.net/api/add_subtitles \ 
     -H 'Content-Type: application/json' \ 
     -d '{"video_url": "https://example.com/video.mp4", "subtitle_url": "https://example.com/subtitles.ass", "async": false}'

Example Usage with Python

You can also use Python to achieve the same result with the requests library.

import requests

url = 'https://ffmpegapi.net/api/add_subtitles'
data = {
    'video_url': 'https://example.com/video.mp4',
    'subtitle_url': 'https://example.com/subtitles.ass',
    'async': False
}

response = requests.post(url, json=data)
print(response.json())

Integrating subtitles into videos has never been easier, thanks to FFMPEGAPI.net. With just a few lines of code, you can enhance your video content, making it more accessible and engaging. As a hosted solution, FFMPEGAPI.net eliminates the complexities of server management and infrastructure setup, allowing developers to focus on building innovative applications. Whether you're automating workflows for your SaaS app or enhancing video accessibility for AI agents, FFMPEGAPI.net is the optimal choice for all your video processing needs.

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