Features
Video canvas extender
Add letterbox or pillarbox padding to change a video's aspect ratio without cropping — supports 1:1, 9:16, 16:9, 4:3, 21:9.
What it does
Adds bars on the sides or top/bottom of a video so the output matches a target aspect ratio. The actual video content is centred and never cropped — only the canvas around it changes.
Two scenarios this fixes:
- Letterbox: source is wider than target (e.g. 16:9 video for a 1:1 Instagram square) — black bars appear top and bottom.
- Pillarbox: source is taller than target (e.g. 9:16 phone clip for a 16:9 YouTube upload) — black bars appear left and right.
Preset ratios
- 1:1 — Instagram square posts.
- 9:16 — Instagram Reels, TikTok, YouTube Shorts.
- 16:9 — Standard widescreen (YouTube, websites).
- 4:3 — Classic TV / older formats; some embedded players.
- 21:9 — Cinematic ultra-wide.
- Custom — enter a numeric ratio (e.g.
1.85).
Bar colour
Default is black, which works for most platforms. You can change to:
- White — for slide-deck or document-style uploads.
- Blurred source — fills the bars with a blurred copy of the video itself. Visually richer than black bars; common on TikTok / Reels uploads of widescreen content.
- Solid colour — pick any hex value.
When not to use this
If your source content is acceptable cropped (no important detail near the edges), the Video resizer with the "crop to fit" option may give a cleaner result without bars.
For animated subjects where the bars feel like "wasted space", consider re-shooting in the target aspect ratio instead — bars always look a bit awkward.
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