📐 Resolution & Aspect Ratio Calculator

Calculate any aspect ratio in seconds

Whether you're sizing an Instagram post at 4:5, exporting a YouTube video at 16:9, or figuring out the right dimensions for a new monitor, our aspect ratio calculator does the math in real time.

Enter any width or height, pick a ratio, and get precise pixel-perfect dimensions instantly. No downloads, no sign-ups, no guessing.

What Is an Aspect Ratio Calculator?

An aspect ratio calculator is a tool that converts between width and height values based on a given ratio. If you know one dimension, the calculator instantly computes the other — keeping the proportions exactly right for photos, videos, screens, or design projects.

Ratios like 4:5, 16:9, 1:1, and 21:9 describe how the width compares to the height. Our dimension ratio calculator handles all the common formats plus any custom ratio you throw at it — no manual math required.

Why Use Our Aspect Ratio Calculator?

Our tool is designed for speed, precision, and flexibility. Here's why creators, designers, and gamers choose it:

• Instant Calculations: Results update live as you type — no "calculate" button to click.
• Common Ratios Built-In: One-click presets for 4:5, 16:9, 9:16, 1:1, 4:3, 21:9, and more.
• Custom Ratio Support: Enter any ratio you need — perfect for unusual formats and print dimensions.
• Pixel-Precise Output: Accurate down to the last pixel for design, video, and photography work.
• Works on Every Device: Desktop, laptop, tablet, or phone — the calculator adapts instantly.
• 100% Free: No sign-ups, no paywalls, no limits.

How to Use the Dimension Ratio Calculator

Calculating any ratio takes less than 15 seconds:

1. Pick Your Aspect Ratio: Choose from 4:5, 16:9, or enter a custom value.
2. Enter One Dimension: Type your known width OR height (not both).
3. Get the Missing Value: The calculator fills in the matching dimension instantly.
4. Copy or Apply: Use the calculated values directly in your design software, export settings, or dimension specs.
5. Try Different Ratios: Change the ratio to see how your content will look in multiple formats.

4:5 Ratio Calculator — For Instagram & Portrait Content

The 4:5 aspect ratio is the tallest ratio Instagram allows in feed posts, which is why it's become the go-to format for creators who want maximum visibility. Our 4:5 ratio calculator handles it in one click.

Common 4:5 dimensions:

• 1080 × 1350: Standard Instagram portrait post size
• 1200 × 1500: Higher-res version for crisp mobile display
• 2160 × 2700: 4K-quality exports for premium content
• 800 × 1000: Smaller web-optimized version

Use 4:5 for Instagram feed photos, Pinterest pins, and any portrait-oriented social media content where you want to dominate vertical screen space.

16:9 Aspect Ratio Calculator — For Video & Widescreen

16:9 is the universal widescreen standard — used by YouTube, Netflix, TV broadcasts, and nearly every modern monitor. Our 16:9 aspect ratio calculator handles every common resolution.

Common 16:9 resolutions:

• 1280 × 720: HD (720p) — basic video quality
• 1920 × 1080: Full HD (1080p) — YouTube and streaming standard
• 2560 × 1440: QHD (1440p) — modern gaming monitor sweet spot
• 3840 × 2160: 4K UHD — premium video and display standard
• 7680 × 4320: 8K UHD — emerging high-end format

Use 16:9 for YouTube videos, Twitch streams, presentations, desktop monitor setups, and any content meant for widescreen playback.

Common Aspect Ratios Explained

Different ratios serve different purposes. Here's a quick reference to the ones you'll use most:

• 1:1 (Square): Instagram feed posts, profile pictures, album covers. Common size: 1080 × 1080.
• 4:5 (Portrait): Instagram portrait feed, Pinterest. Common size: 1080 × 1350.
• 9:16 (Vertical): Instagram Stories, Reels, TikTok, YouTube Shorts. Common size: 1080 × 1920.
• 16:9 (Widescreen): YouTube, TV, monitors, presentations. Common size: 1920 × 1080.
• 4:3 (Classic): Older TVs, iPad screens, some legacy content. Common size: 1024 × 768.
• 21:9 (Ultrawide): Ultrawide monitors, cinematic video. Common size: 2560 × 1080 or 3440 × 1440.
• 32:9 (Super Ultrawide): Super-ultrawide gaming monitors. Common size: 5120 × 1440.
• 2.39:1 (Cinematic): Theatrical films, cinematic YouTube content.
• 3:2 (Photo): DSLR and mirrorless camera photography. Common size: 6000 × 4000.

Display Ratio Calculator — For Monitors & Screens

Buying a new monitor or building a multi-display setup? Our display ratio calculator helps you figure out screen dimensions and pixel coverage at a glance.

Popular display ratios and their uses:

• 16:9: Standard office, gaming, and home monitors — most common ratio sold today.
• 16:10: Productivity-focused monitors and laptops — offers slightly more vertical space than 16:9.
• 21:9: Gaming ultrawides — expanded field of view for racing, flight sims, and cinematic games.
• 32:9: Super ultrawide gaming and multitasking monitors — equivalent to two 16:9 displays side by side.
• 3:2: Surface laptops and high-end productivity screens — great for documents and web browsing.
• 18:9 / 19.5:9 / 20:9: Modern smartphone display ratios.

Use the display ratio calculator to figure out exact pixel counts when comparing different monitor sizes and resolutions.

Who Uses an Aspect Ratio Calculator?

• Content Creators: Instagram, TikTok, and YouTube creators who need exact dimensions for each platform.
• Photographers: Cropping shots to specific ratios for prints, social media, or portfolios.
• Video Editors: Exporting videos at the right aspect ratio for each target platform.
• Graphic Designers: Sizing banners, posters, social posts, and marketing content.
• Web Developers: Calculating image placeholder dimensions and responsive design values.
• Gamers: Configuring monitor resolutions, in-game FOV, and stream overlays.
• Print Designers: Sizing posters, business cards, flyers, and other print materials.

Tips for Choosing the Right Aspect Ratio

• Match the Platform: Each social platform has a preferred ratio. Use our calculator to nail it on the first export.
• Shoot Higher, Crop Down: Capture at a wider ratio, then crop to platform requirements. This gives you more flexibility.
• Check Mobile First: Most social content is viewed on phones — portrait ratios (4:5, 9:16) usually perform better.
• Avoid Stretching: Never stretch content to fit a ratio. Always crop or add padding to preserve the original proportions.
• Consider Print vs Screen: Print usually uses 3:2 or 4:5; screens use 16:9 or 9:16. Plan the ratio before you design.
• Future-Proof Your Content: Shoot in 16:9 when possible — it's the most versatile source ratio for cropping to other formats.