The complete guide to video aspect ratios in 2026

Aspect ratio is a delivery decision

Aspect ratio is the relationship between width and height. In production, it is not just a visual preference. It determines platform fit, cropping behavior, overlay dimensions, caption safety, and export quality.

• Pick the final platform before choosing the ratio.
• Generate overlays for the final canvas, not the source footage.
• Keep a separate export for each major platform instead of relying on auto-crop.

The core ratios editors actually need

Most FrameGen users can cover their workflow with six ratios: 16:9, 9:16, 1:1, 4:5, 21:9, and 5120x1080. Everything else is usually a variation of those delivery decisions.

Short-form vertical workflow

For TikTok, Reels, and Shorts, use 1080x1920. If the footage is horizontal, decide whether to crop, stack, or letterbox. A transparent PNG frame helps create an intentional cinematic strip instead of an accidental empty area.

• Use 9:16 as the export canvas.
• Keep subjects and captions away from app UI zones.
• Use letterbox or film border overlays when preserving horizontal footage.

Widescreen and cinematic workflow

For YouTube and client-facing edits, 16:9 remains the baseline. If you want a film look, use a 21:9 matte inside a 16:9 export or publish a true ultra-wide asset when the platform supports it.

• Use 1920x1080 or 3840x2160 for standard YouTube delivery.
• Use 21:9 mattes when you want the cinematic feel without changing the full canvas.
• Use 5120x1080 when the ultra-wide strip itself is the creative idea.

Common mistakes

Most ratio problems are caused by mixing the source clip ratio with the delivery ratio. Your camera footage, editing sequence, overlay PNG, and final export are separate decisions.

• Do not stretch horizontal footage to vertical; crop or frame it.
• Do not resize a 16:9 overlay into a 9:16 export; generate a 9:16 overlay.
• Do not put captions under letterbox bars unless the bars are intentionally used as title space.
• Do not trust platform previews without checking the posted safe zones.

FrameGen implementation

Use FrameGen as the ratio lock before editing. Pick the final size, preview the frame, then export a transparent PNG. That file becomes a visual contract for the edit.

• Choose the preset closest to the final platform.
• Use custom width and height for exact client specs.
• Download the PNG and place it above the timeline footage.
• Repeat for each platform-specific export.