How to Add Subtitles to a Video for Instagram

The fastest way to add subtitles to a video for Instagram is to decide first whether you want the platform's captions or your own, then, if it's your own, transcribe the audio and burn them into the picture before uploading. Here's how each route works.

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Add subtitles to a video for Instagram: the platform's route

Instagram's Help Center describes automatic closed captions generated with speech recognition, where the speech in the reel is written out as text at the bottom of the video.

That's a real, free feature and for a lot of clips it's enough. Two things to know about it. First, it's the platform producing and displaying the text, which means it's rendered by Instagram rather than being part of your video file. Second, "at the bottom" is a fixed decision. You don't get to move it out of the busiest part of the frame.

What the audio track has to be

Whatever generates captions , Instagram's recogniser or one you run yourself , is reading an audio track, and Meta's publishing documentation specifies what that track is: AAC, 48 kHz sample rate maximum, one or two channels.

Nothing exotic, but it's worth knowing that the audio is the input. Speech recognition accuracy is decided by what the microphone captured and how cleanly it was encoded, long before any software gets involved. A muddy, noisy track produces bad captions on every system there is.

Transcription that happens on your device

Montaj's route to subtitles starts with on-device transcription using WhisperKit. The audio is read locally, and it isn't uploaded anywhere to be processed.

From that transcript it generates word-by-word karaoke captions where each word carries its own timing, which is what makes two things possible. You can correct a name, a product or a piece of jargon directly in the text and the timing follows the correction, so nothing needs re-syncing by hand. And the finished captions are burned into the image at export , 1080×1920, no watermark , so they're part of the picture in whatever file you upload, styled the way you set them rather than the way a player decides. When you add subtitles to a video for Instagram this way, they stop being a platform feature and start being part of the video.

Adding subtitles to a video for Instagram in 4 steps

  1. 1

    Decide between platform captions and burned-in captions

    Instagram can generate captions from the speech in your reel. Burned-in subtitles are part of the picture instead. They show up wherever the file goes, including off Instagram.

  2. 2

    Transcribe the audio first

    Every subtitle starts as a transcript. Montaj transcribes the audio track on your device, so nothing is sent anywhere to be read.

  3. 3

    Turn the transcript into word-by-word captions

    Karaoke-style captions are generated from the transcript, with each word carrying its own timing rather than sitting in a fixed block.

  4. 4

    Correct the words, then burn them in

    Fix a name or a piece of jargon directly in the text. The word-level timing follows the correction. Then export with the captions part of the image.

The verdict

If the clip only ever lives on Instagram and the stakes are low, use the automatic captions. They're free, they're instant, and they're genuinely decent. I'd burn subtitles in for anything that matters: a clip you'll also post elsewhere, anything with a brand name or jargon that speech recognition will mangle, anything where the styling is part of the point. Burned-in captions are part of the picture, which means they're yours, right down to the spelling.

Chloé, Senior Video Editor

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Frequently asked questions

How do I add subtitles to a video for Instagram for free?
Instagram can generate automatic captions from the speech in a reel at no cost. To get captions that are part of the picture and travel with the file, transcribe the clip and burn the subtitles in before uploading.
Does Instagram add captions automatically?
Instagram's Help Center describes automatic closed captions using speech recognition, with the speech in the reel written out as text at the bottom of the video.
Are burned-in subtitles better than Instagram's automatic captions?
They behave differently. Automatic captions are generated and displayed by the platform. Burned-in subtitles are part of the image, so they appear identically wherever the file is played and don't depend on the player showing them.
What audio format does Instagram expect for a reel?
Meta's publishing documentation specifies AAC, at a maximum 48 kHz sample rate, in one or two channels. That's the track any speech recognition , Instagram's or your own , will be working from.