Aspect Ratio Calculator Online Free

Calculate aspect ratios for images and videos

Calculate Ratio

Width

Height

16:9

Ratio

1.7778

Decimal

Scale Dimensions

New Width

New Height

Aspect Ratio Calculator Online Free - Calculate Image Ratios

Calculate aspect ratios for images and videos online free. Enter width and height to get the ratio as a fraction (e.g. 16:9) and decimal. Scale dimensions while maintaining the aspect ratio — enter a new width to calculate the proportional height, or vice versa. Perfect for responsive web design, video production, social media image sizing, and print design.

Key Features

Calculate ratio from width and height

Shows ratio as fraction (e.g. 16:9)

Shows ratio as decimal (e.g. 1.7778)

Scale width from height proportionally

Scale height from width proportionally

Instant calculation with no delay

Common ratio reference (16:9, 4:3, 1:1)

Clean two-panel layout

Free, no registration required

Why Calculate Aspect Ratios?

Aspect ratios are fundamental to visual design. Maintaining the correct ratio prevents distortion when scaling images or videos. Web developers need to know ratios for responsive images and video embeds. Video producers need to match platform requirements (YouTube is 16:9, Instagram Stories is 9:16). Photographers need to crop images to specific ratios for printing. Designers need to scale mockups proportionally without distortion.

Benefits

•Resize images without distortion or stretching
•Plan video dimensions for different platforms
•Design responsive layouts with correct proportions
•Calculate print dimensions for photos and posters
•Verify image ratios before uploading to social media
•Scale UI mockups proportionally in design tools

How to Calculate Aspect Ratio

1Enter the original width in the Width field
2Enter the original height in the Height field
3View the ratio (e.g. 16:9) and decimal instantly
4To scale: enter a new width and click '→ H'
5Or enter a new height and click '→ W'
6The proportional dimension is calculated automatically

Common Aspect Ratios Reference

16:9 (1.778) — HD/4K video, YouTube, most monitors. 4:3 (1.333) — traditional TV, iPad. 1:1 — Instagram square posts, profile pictures. 9:16 (0.5625) — Instagram/TikTok Stories, vertical video. 3:2 (1.5) — DSLR photos, 35mm film. 21:9 (2.333) — ultrawide monitors, cinematic video. 1.91:1 — Facebook/LinkedIn link previews. A4 paper: 1:1.414 (√2).

Frequently Asked Questions

What is 16:9?

16:9 is the standard widescreen aspect ratio used for HD and 4K video, most monitors, and YouTube. 1920×1080 and 3840×2160 are both 16:9.

What aspect ratio should I use for social media?

Instagram posts: 1:1 (square) or 4:5. Stories/Reels: 9:16. Twitter/X: 16:9. Facebook: 1.91:1.

How do I maintain aspect ratio when resizing?

Enter the new width and click '→ H' to calculate the proportional height, or enter the new height and click '→ W' for the width.

What is 4:3?

4:3 is the traditional TV and monitor aspect ratio. Common resolutions: 640×480, 800×600, 1024×768.

What is the aspect ratio of A4 paper?

A4 paper is 210×297mm, giving an aspect ratio of approximately 1:1.414 (√2). This is the ISO 216 standard used for most paper sizes.

Related Keywords

aspect ratio calculatorimage aspect ratiovideo aspect ratioratio calculator onlinescale dimensionsimage resize calculatorproportional scaling16:9 calculator

Hợp tác ngay với Tấn Phát Digital

Chúng tôi không chỉ thiết kế website, mà còn giúp doanh nghiệp xây dựng thương hiệu số mạnh mẽ. Cung cấp dịch vụ thiết kế website trọn gói từ thiết kế đến tối ưu SEO. Hãy liên hệ ngay với Tấn Phát Digital để cùng tạo nên những giải pháp công nghệ đột phá, hiệu quả và bền vững cho doanh nghiệp của bạn tại Hồ Chí Minh.

Công cụ Calculator Tools liên quan

Age Calculator

Tính tuổi online, cung hoàng đạo, con giáp.

Aspect Ratio Calculator

Tính tỷ lệ khung hình.

BMI Calculator

Tính BMI online, calo, protein.

Discount Calculator

Tính giảm giá, khuyến mãi.

Loan Calculator

Tính khoản vay, lãi suất.

Mortgage Calculator - Tính Vay Mua Nhà Online

Tính trả góp vay ngân hàng Việt Nam (lãi cố định/giảm dần).

Investment Calculator - Tính Lợi Nhuận Đầu Tư

Tính lãi kép, cổ phiếu, tiết kiệm ngân hàng.

Retirement Planner - Lập Kế Hoạch Hưu Trí

Dự tính số tiền cần cho tuổi nghỉ hưu.

Tax Calculator VN - Tính Thuế Thu Nhập Cá Nhân

Tính thuế TNCN 2026 theo quy định Việt Nam.

Overtime Calculator

Tính lương làm thêm giờ.

Percentage Calculator

Tính phần trăm nhanh.

Simple Calculator

Máy tính cơ bản.