How to Add Captions to a Screen Recording in Chrome (2026)

You want the screen recording to work with the sound off and to turn up when someone searches its words. Both come from captions. As of August 2026 there are two free ways to get them in Chrome, and they produce different objects: a subtitle file you attach to the video, or caption text rendered into the picture. The second one now runs entirely on your own machine, model included, which is new. Pick by the output you need and you avoid the wrong tool.

Routes re-verified August 2026 against SuperchargeCapture 1.1.1’s shipping source, including the bundled Whisper tiny.en transcriber; the YouTube auto-caption SRT round-trip was tested on Chrome 150.

Soft Captions vs Burned-In: Pick Before You Start

The choice shapes every step after it, so make it first.

If the clip is going somewhere with a caption toggle, keep it soft and flexible. If it will autoplay in a feed or a chat where no CC button exists, burn it in so the words cannot be lost. Plenty of screen recordings end up needing both versions.

Caption Without Uploading: The On-Device Routes

For years the private path meant typing subtitles by hand. Speech models small enough to ship inside a browser extension changed that:

• Transcribe locally in SuperchargeCapture. Record the tab, open the recording in the editor, click Transcribe. A Whisper tiny.en model packaged in the extension turns the speech into timed cues while a progress bar runs. Remote model fetching is switched off in the code, so nothing is downloaded and nothing is sent: the audio and the transcript stay on your machine, and the first transcription after install works with no connection at all. The model is English-only, which is the price of shipping it inside an extension.
• Type the SRT yourself. For a clip under a minute, writing the subtitle file by hand is quick and fully local. The format is plain text: an index, a 00:00:01,000 --> 00:00:04,000 timecode, then the line.
• Chrome Live Caption. Turn it on under Settings → Accessibility → Captions → Live Caption. Chrome then captions any audio playing in the browser in real time, processed on your device, never uploaded. The limit worth knowing: it captions live playback for the viewer and cannot export an SRT, so it is for watching with captions, not for attaching them to a file.

The local automatic route gives you captions rendered into the video. When what you need is the subtitle file itself, the next route is still the free way to get one.

The Free SRT Route: Auto-Caption on YouTube, Then Edit

Let a machine draft the text and fix the draft yourself. YouTube does this well and for free:

1. In YouTube Studio, upload the recording as an unlisted video.
2. Wait for processing, then open Subtitles. You will see a track tagged (Automatic).
3. Click Duplicate and Edit to turn the auto-track into a correctable draft. Fix the timing, the product names, and anything the machine misheard.
4. Use Options → Download to save the track as an SRT.

You now have a real subtitle file. Attach it as soft captions on any player that accepts SRT, or feed it to a tool that burns it into the video. One cost comes with this route. The video has to go up to YouTube first, so it suits public or non-sensitive recordings. For anything private, transcribe on-device or type the file yourself.

Record and Caption in the Same Window

Every route starts with the recording, and the recording decides your options. A local file you own can go to any captioner, or none. A file trapped in a cloud recorder’s account can only be captioned that recorder’s way. SuperchargeCapture keeps you in the first camp and then closes the loop itself.

It records the current tab through chrome.tabCapture with no screen-picker, mixes tab audio and your microphone, and writes the video to your device as MP4, WebM, or GIF. Open that recording in the editor and Transcribe produces the caption track. What you get is a draft, and the editor treats it as one: click a cue to jump the video to that moment, retype the line, drag its start and end times, delete the ones you do not want, or re-transcribe from scratch. A Show captions toggle controls whether the track appears at all. On export, the active cue draws as white text on a dark rounded pill near the bottom of the frame, rendered into the file locally along with everything else.

Two honest limits. The bundled model handles English only, so a narration in another language will not transcribe usefully. And there is no SRT download here: the captions become part of the video rather than a separate track a viewer can switch off. For a demo clip headed to Slack or a feed, that is the format you wanted anyway.

Loom vs Local: Where Your Video and Its Captions Live

Cloud recorders auto-caption too. The difference is where the transcription happens:

Cloud captions are convenient because the video is already on the vendor’s servers. That is fine for public demos and a real problem for a recording you cannot upload. Running the model locally trades language coverage and the SRT download for a clip that never leaves your machine.

Which Caption Route Fits Your Clip

Pick by the clip in front of you:

• English narration that must stay private → transcribe on-device in the editor, fix the cues, export.
• Public demo or tutorial that needs a searchable transcript → upload to YouTube, auto-caption, Duplicate and Edit, download the SRT.
• Autoplaying in a feed or Slack → captions rendered into the video, so no missing CC toggle can hide them.
• Another language, or you need the SRT file itself → the YouTube round-trip, or type the file by hand for a short clip.
• You only need to watch it captioned → turn on Chrome Live Caption; it stays on-device.

If your recordings need captions and some of them are too sensitive to upload, do the whole job locally. SuperchargeCapture records the tab or screen to a file you own and transcribes it with a model that ships inside the extension, free and with no account, so the audio never has to reach anyone’s server to become text.