AI Video Aspect Ratio & Resolution Calculator

Pick the right aspect ratio and resolution for every platform before you generate. This free AI video aspect ratio calculator shows the recommended dimensions, frame rates and safe-zone tips for TikTok, Instagram Reels, YouTube Shorts, YouTube, X and square feed posts — then lets you solve any custom resolution. Enter a width, choose a target ratio like 16:9 or 9:16, and instantly get the matching height plus the simplified ratio.

Getting the aspect ratio right keeps your AI video sharp, full-screen and free of letterboxing or awkward crops. Everything runs in your browser: no login, no limits, no cost.

Recommended aspect ratios by platform

PlatformRatioResolutionFPSNotes
TikTok9:161080×192024–60Vertical full-screen. 4K uploads downscale to 1080p.
Instagram Reels9:161080×192030Keep key action inside the centre safe zone.
YouTube Shorts9:161080×192024–60Up to 3 minutes, vertical.
YouTube (landscape)16:91920×108024–60Standard horizontal video.
X / Twitter16:91280×72030–6016:9 or 1:1 both display well.
Square (feed)1:11080×108030Great for in-feed posts.

Custom resolution solver

Width
1920
Height
1080
Simplified ratio
16:9

At 1920px wide, a 16:9 video is 1920×1080 (16:9).

How to use this tool

  1. Check the platform table for the recommended ratio, resolution and frame rate.
  2. In the custom solver, enter the width in pixels you want to work with.
  3. Choose a target aspect ratio (16:9, 9:16, 1:1, 4:5 or 21:9).
  4. Read off the computed height and simplified ratio to set up your render exactly.

Frequently asked questions

What aspect ratio should I use for TikTok and Reels?
Use 9:16 vertical at 1080×1920 for TikTok, Instagram Reels and YouTube Shorts. Keep your key action inside the centre safe zone so on-screen UI does not cover it.
How does the resolution solver work?
Enter a width and pick a target ratio. The tool calculates the exact height that keeps that ratio, then shows the simplified ratio of your final width × height so you can confirm it matches your target.
What is the best aspect ratio for YouTube?
Standard landscape YouTube videos use 16:9 at 1920×1080 (1080p) or higher. For YouTube Shorts, switch to 9:16 vertical instead.

Related free tools

8-Second Scene Splitter
Break a long scene into stitchable 8-second shots with continuity notes.
Character Consistency Builder
Build a reusable character block so faces stay consistent across clips.
Veo 3 Prompt Generator
Build cinematic Veo 3 prompts from camera, lighting & style controls.

More on VEO 4

VEO 4 PricingVEO 4 APIHow to Use VEO 4VEO 4 vs VEO 3All Free Tools

Ready to generate your VEO 4 video?

Take your prompt straight into VEO 4 Gen — the cheapest VEO 4 access online, from $0.06/sec.