Guide
How to caption UGC ads
Not everyone scrolls with the sound on, and an ad they can't follow is an ad they skip. Captions turn your spoken hook into something a muted viewer can read in the moment it's on screen. Here's how to caption UGC ads so they're accurate, readable and out of the way of the app's own buttons.
The short version
- Burn captions into the video, so they look the same everywhere the ad runs.
- Show a few words at a time, timed to the speech, rather than whole sentences.
- Keep them clear of the feed's buttons and the caption text at the bottom of the screen.
- Use high contrast and one consistent style; highlighting each word as it's spoken helps the eye follow.
- Check every product name and number by hand. Automatic captions are good, not perfect.
Why do UGC ads need captions?
Because the hook has to land whether the sound is on or not. TikTok's split testing guide (opens in a new tab) calls the opening 2–3 seconds the hook, and Meta reports 3-second video plays (opens in a new tab) as a metric of its own. A muted viewer who can read your opening line in that window has a reason to stay.
Should you burn in captions or use the platform's?
| What | Burned in | The platform's own |
|---|---|---|
| Look | Exactly the style you chose | The app's style |
| Where they show | Everywhere the file goes | Only on that platform |
| Fixing a word | Edit and export again | Depends on the platform |
| Placement | You choose it | The app chooses it |
For ads that run on more than one platform, or that you deliver to a brand as files, burned-in captions are the safer choice: the file carries them.
How many words should each caption show?
A few. Short chunks timed to the speech are easier to read than full sentences, and they keep the eye near the speaker. Break lines at natural pauses, keep a phrase like a product name on one line, and never leave a caption on screen after the words have been said.
Where should captions go on a vertical ad?
On a 9:16 ad, the feed covers parts of the frame: buttons down the right side, and the account name and ad text along the bottom. Place captions in the open middle, above the bottom text and left of the buttons, and never over your face or the product.
How should you style captions?
- Contrast first. Light text with a dark outline or shadow, or dark text on a light box, reads on any background.
- One style for the whole ad. Changing fonts or colours mid-ad looks like a mistake.
- Highlight the word being said. It helps the eye keep pace with the speaker.
- Consistent capitalization and punctuation. Pick sentence case or all caps, and stick to it.
- Big enough on a phone. Check the ad on a phone, not a monitor.
How does Mashcut caption UGC ads?
Mashcut burns in captions made from your own words in every ad, placed clear of the feed's buttons, in a 9:16 file at 1080×1920. You can change any caption before you export.
In the web editor you can also set the captions' size, colour and place, their capitalization and punctuation, how many words each one shows, and whether each word lights up as it's spoken.
Frequently asked questions
Do captions help ads perform?
They make the ad readable with the sound off, which matters most in the opening seconds. Whether they lift your results is worth testing on your own account.
Should captions be in all caps?
Either works. Pick one style and keep it for the whole ad.
Can I fix a wrong word in Mashcut's captions?
Yes. Change any caption before you export; exporting again after an edit doesn't use a credit.
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