Caption font preview

What makes a caption font easy to read

This part is advice, not a rule from any app. The font matters less than people think. Any plain, upright font without little feet on the letters (a sans-serif) reads well on a phone: Arial, Helvetica, Inter, Montserrat, TikTok Sans. Thin, script and narrow fonts are the ones that fail, because a phone is small and the video behind the words keeps moving.

Weight matters more. Use bold or heavier. A regular weight that looks fine in your editor turns thin and grey once the video is squeezed for upload.

Then contrast. White letters with a dark shadow, a dark outline or a dark box behind them stay readable over almost any shot. Web guidelines ask for a contrast of at least 4.5 to 1 between text and what's behind it, or 3 to 1 for large text. A video changes every frame, so the shadow or box is what keeps you above that line when you walk past a window.

Coloured letters are fine for one word at a time. A whole sentence in yellow or pink is harder to read than white.

How big, and how many words

For a sentence-style caption, a text size of about 5 to 6% of the video's width works well: roughly 55 to 65 pixels on a 1080-pixel-wide video. For one or two words at a time you can go to 8 to 10%. Much smaller and people squint; much bigger and the words cover your face.

Keep each caption short. Three to five words can be read in one glance without the eyes leaving your face for long. One or two words at a time feels fast and suits a hook. Seven or more turns the caption into a paragraph, and people stop listening to read it.

Break lines where you'd breathe. A caption that ends at a full stop or a pause feels in step with your voice. One that splits “a” from its noun feels wrong even when nobody can say why.

Where to put captions so the app doesn't cover them

Reels, TikTok and Shorts all draw your account name, the description and a column of buttons over the bottom of the video. On an upright video that is about the bottom 34 to 35% of the height, plus a strip down the right side.

So the classic subtitle spot, right at the bottom, is the worst place for captions on a phone. Just below the middle of the frame is safer: under your chin if you're filming your face, above the app's own text. Keep them a little left of centre too, clear of the buttons.

The preview starts captions there, in the spot Krafto uses: the part of the frame that is clear on Reels, TikTok and Shorts alike. A longer caption grows upward, away from the app's text. Open “Show what the app covers”, pick an app, and try “Bottom edge” to see what gets hidden. The safe zone checker has the exact numbers for each app and a guide you can download.