Free Aspect Ratio Calculator

About the Aspect Ratio Calculator

Free aspect ratio calculator for TikTok, Reels, Shorts & YouTube video ads. Instantly solve width, height, or crop ratio — no signup needed.

Every calculation and generation runs entirely in your browser - free, instant, nothing uploaded. The hard part is what comes next: filming it. Once your aspect ratio is ready, Creetr shoots it with an AI actor and exports a ready-to-post ad in about two minutes - no camera, no creator fees.

Frequently asked questions

What aspect ratio should I use for TikTok and Reels?+

Use 9:16 (vertical) for TikTok, Instagram Reels, and YouTube Shorts. This aspect ratio is crucial because it completely fills the user's mobile screen, eliminating distracting black bars and significantly enhancing viewer engagement. When your ad takes up the entire screen, viewers are more likely to watch it all the way through, which directly impacts watch time and completion rates. These metrics are key signals that the platform's algorithm uses to determine which content to promote, meaning a 9:16 aspect ratio helps your ads reach a wider audience more effectively.

Is 16:9 or 9:16 better for video ads?+

For video ads on Creetr, 9:16 is generally better because it’s optimized for vertical feeds where most short-form content is consumed. This includes platforms like TikTok, Instagram Reels, Facebook Stories, and YouTube Shorts, where viewers are scrolling vertically. A 9:16 aspect ratio takes up more screen real estate, making your ad more prominent. While 16:9 is still relevant for places like YouTube in-stream ads or desktop landing pages, most successful AI-UGC campaigns on Creetr leverage a 9:16 master creative. You can then easily repurpose this into 1:1 or 16:9 versions for broader feed placements to maximize reach and engagement across different viewing environments.

How do I calculate the missing width or height for a ratio?+

Divide the ratio's width by height to get a multiplier, then apply it to your known dimension. For 9:16 at 1080px wide: 1080 / 9 x 16 = 1920px tall. This tool does that math instantly — just enter one dimension and pick your target ratio.

What's the best aspect ratio for Instagram feed posts?+

The best aspect ratio for Instagram feed posts is 4:5 (1080x1350px) because it takes up more vertical space in the feed, leading to better reach than the traditional 1:1 (square) format. While 1:1 still maintains a clean look for your grid, the taller 4:5 ratio is more likely to capture attention as users scroll. This increased visibility often translates to more impressions and engagement for your short-form video ads on Creetr. Remember to use 9:16 for Reels and Stories to maximize their performance within those specific formats.

Does aspect ratio affect ad performance and cost?+

Yes, aspect ratio significantly impacts your ad performance and cost on platforms like Creetr. When your video doesn't match the optimal aspect ratio, such as 9:16 for full-screen mobile viewing, platforms may automatically reject it or add black bars, which visually disrupts the viewer experience. This disruption leads to lower click-through rates (CTR) because users are less likely to engage with a video that feels out of place. Furthermore, a lower CTR can signal to the ad platform that your ad isn't resonating, often resulting in a higher cost per thousand impressions (CPM) as the platform seeks to show your ad to a more receptive audience. Native, full-screen 9:16 UGC ads, designed to blend seamlessly with organic content, consistently outperform those with letterboxing or cropping by avoiding the "ad" look and feel, thereby driving better engagement and potentially lower costs.