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Change video aspect ratio by adding padding for Instagram, YouTube, TikTok, and more.

The problem

Horizontal footage doesn't work for TikTok (9:16) and vertical footage looks wrong on YouTube (16:9). Black bars added by posting platforms look unprofessional and are sometimes cropped. You need to control the framing yourself.

The NSS solution

NSS Video Canvas Extender adds a configurable padding color around your video to reach the target aspect ratio — 1:1, 9:16, 16:9, 4:3, 21:9, or custom. Your subject stays centered and full size.

How to use it

  • 1

    Make horizontal videos into Instagram squares

    Add top and bottom padding to convert 16:9 horizontal footage to 1:1 square for Instagram feed posts without cropping your subject.

  • 2

    Convert landscape to portrait for Reels and TikTok

    Add side bars to make a 16:9 clip into 9:16 for Stories, Reels, and TikTok — keeping the original framing while meeting format requirements.

  • 3

    Add cinematic black bars

    Add top and bottom black bars to convert 16:9 to 21:9 for a cinematic film look in video essays, travel vlogs, and narrative projects.

Step-by-step guide

  1. 1

    Choose the target aspect ratio

    Pick from 1:1, 4:3, 16:9, 9:16, 4:5, 21:9, or enter a custom ratio.

  2. 2

    Choose a padding color

    Black for cinematic look, white for a clean studio feel, or any custom hex color to match your brand.

  3. 3

    Upload and download

    Processing plays through at real time. Download the padded video when complete.

Common questions

Does this crop my video?

No — the canvas extender only adds padding. Your subject is never cropped. The tool scales the canvas out around your video.

What aspect ratios are supported?

1:1, 4:3, 16:9, 9:16, 4:5, 21:9, and custom. Enter any W:H ratio for a custom canvas.

Ready to try it?

No account. No subscription. No images uploaded to any server.

Extend video canvas free

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