New ReleaseAspect Ratio & Resolution Suite 2.0.

Aspect ratio and resolution calculator.

A developer-first, pixel-perfect tool to simplify aspect ratios, solve missing dimensions, compare screen viewports, and calculate screen DPI/PPI in real time.

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Calculate dimensions

Aspect Ratio Presets
Quick Platform Presets
Monitor densities

PPI / DPI Calculator

Pixel Density81.59 PPI
Dot Pitch0.3113 mm
Monitor Dimensions23.53" × 13.24"
Total Viewport Area311.5 sq in
Total Pixel Volume2.07 Million Pixels (Megapixels)

Aspect Ratio Visualizer

Simulated responsive scaling and cropping boundaries

1920 × 108016:9 Widescreen

Export Code & Formats

CSS Stylingaspect-ratio: 16 / 9;
Tailwind v4 Classesaspect-[16/9]
HTML Dimensionswidth="1920" height="1080"
JSON Specifications{"w": 1920, "h": 1080, "ratio": "16:9"}

Resolution Scaling Map

Standard pixel scale combinations for the current aspect ratio

Resolution LabelWidth × HeightMegapixelsAction
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Complete Guide

The Ultimate Free Resolution Calculator

Everything you need to know about image resolution, screen resolution, aspect ratios, DPI, and pixel density — and how our free online resolution calculator makes the math effortless.

Whether you are a web designer sizing a banner, a video editor encoding a YouTube upload, a photographer exporting a print file, or an AV engineer planning an LED wall installation, getting resolution right the first time saves hours of rework. Our free resolution calculator — also called a screen resolution calculator, image resolution calculator, and display resolution calculator — handles every scenario in one streamlined tool. No sign-up, no watermarks, no cost.

Below we explain exactly what resolution and aspect ratio mean, how the calculations work, and why our tool is the fastest way to get precise answers for projects of any size.

What is a resolution calculator?

A resolution calculator is an online tool that converts between pixel dimensions, aspect ratios, and pixel density values (PPI / DPI). Given any two known values — such as a width in pixels and a target aspect ratio — it instantly solves for the missing dimension. You can also work in reverse: enter a width and height and let the aspect ratio calculator reduce the ratio to its simplest form using the Greatest Common Divisor (GCD) algorithm.

Our tool covers four core modes:

  • Dimension Solver — enter width, height, or ratio to find missing values.
  • Ratio Finder — reduce any resolution to its simplest aspect ratio form.
  • DPI / PPI Calculator — calculate pixel density for any screen size.
  • Standard Presets — browse 60+ preset resolutions for every platform.

Image resolution vs. screen resolution

These two terms are often confused. Image resolution describes the total number of pixels packed into a digital image file — for example, a 4000 × 3000 image has 12 megapixels. Use our image resolution calculator to determine the pixel count, megapixel rating, or print size of any photo.

Screen resolution (or display resolution) refers to the number of physical pixels on a monitor or device panel — for example, 1920 × 1080. Use our screen resolution calculator to find what resolution matches a given aspect ratio, or to compare viewports across devices. The display resolution calculator mode can also validate whether your creative assets are sized correctly for a target display.

DPI and PPI: the density calculators

Our built-in DPI resolution calculator computes pixel density from screen diagonal and pixel dimensions. Enter your display size in inches and its resolution, and get an exact PPI reading. This is essential for:

  • Checking whether a display qualifies as "Retina" (generally ≥ 220 PPI at normal viewing distance).
  • Comparing phone displays side-by-side before purchasing.
  • Setting correct DPI values when exporting images for print.

Remember: PPI describes screen pixel density, while DPI (dots per inch) technically refers to printer output. Both are calculated using the same formula: diagonal pixels ÷ physical diagonal size.

How to calculate aspect ratios

An aspect ratio is the proportional relationship between width and height, written as W:H. To reduce a resolution to its simplest ratio, divide both dimensions by their GCD. For example, a 1920 × 1080 display has GCD = 120, giving the universal 16:9 aspect ratio used by YouTube, modern TV broadcasts, and most computer monitors.

# Aspect ratio formula
GCD(1920, 1080) = 120
Width Ratio = 1920 ÷ 120 = 16
Height Ratio = 1080 ÷ 120 = 9
Result → 16:9 aspect ratio

Aspect ratios for every platform

Choosing the right aspect ratio for the right platform is critical. Here is a quick breakdown of the most important ones:

  • 16:9 aspect ratio / YouTube aspect ratio: The standard 16x9 aspect ratio is used by YouTube, Vimeo, most streaming services, and HD TVs. The most common implementation is the 1920 × 1080 aspect ratio (Full HD), followed by 2560 × 1440 (QHD) and 3840 × 2160 (4K UHD).
  • Instagram aspect ratio: Instagram supports multiple ratios depending on format — 1:1 (square post), 4:5 (portrait post), 9:16 (Reels / Stories), and 1.91:1 (landscape feed post). Use our aspect ratio resolution calculator to find the correct pixel dimensions for each format.
  • 4:3 aspect ratio: The classic TV and iPad ratio. Still widely used in photography (DSLRs often shoot 4:3), Zoom calls, and certain social media formats. Typical resolutions include 1024×768 and 1600×1200.
  • 21:9 resolution calculator: Ultra-wide monitors (2560×1080 or 3440×1440) and anamorphic cinema use the 21:9 ratio. Use our 21:9 resolution calculator mode to plan assets for ultra-wide screens or cinematic productions.

LED wall & encoder resolution calculators

Our tool is not just for content creators. AV professionals and broadcast engineers rely on it as both an LED wall resolution calculator and an encoder resolution calculator:

  • LED wall resolution: Enter the LED panel width, height, and pixel pitch to calculate the total pixel dimensions of your video wall. Knowing the exact resolution lets you correctly size your media server output and graphic assets.
  • Encoder resolution: Video encoders require you to set an exact output resolution. An incorrect resolution causes scaling artifacts, letterboxing, or rejection by platform validators. Use the calculator to confirm your encoder output matches your target display exactly.

These professional use-cases are why we built the preset library: search by category (TV broadcast, cinema, digital signage, mobile) and instantly load the correct values.

Common industry standards

RatioCommon ResolutionsPrimary Use Case
16:91920×1080, 2560×1440, 3840×2160YouTube, modern monitors, TV broadcasts
9:161080×1920, 1440×2560TikTok, Instagram Reels, YouTube Shorts
21:92560×1080, 3440×1440, 5120×2160Cinematic movies, ultra-wide gaming monitors
1:11080×1080, 1200×1200Instagram posts, profile icons, web avatars
4:31024×768, 1400×1050, 1600×1200iPad screens, vintage CRTs, retro games
3:23000×2000, 3600×2400DSLR cameras, Microsoft Surface laptops

Why use our resolution calculator?

Unlike generic calculators, our aspect ratio resolution calculator is purpose-built for visual media professionals. It handles edge cases like non-integer ratios, anamorphic formats, and mixed-DPI environments. The preset library covers over 60 standard resolutions including every major social platform, broadcast spec, and display tier — so you never have to memorize numbers again.

Everything runs entirely in your browser. There are no server round-trips, no cookies, no accounts, and no ads. Your pixel math stays private, and results appear in real time as you type. Whether you're confirming a 1920 × 1080 aspect ratio for a client deliverable, planning a multi-panel LED wall resolution, setting your streaming software's encoder resolution, or checking the correct Instagram aspect ratio for your next Reel — this is the only tool you'll need.

Bookmark this page as your go-to screen resolution calculator, image resolution calculator, display resolution calculator, DPI resolution calculator, and aspect ratio calculator — all rolled into one free, fast, and privacy-respecting tool.

FAQ

Frequently asked questions

What size is 1920x1080 resolution?

A 1920x1080 resolution (also known as Full HD or 1080p) has a width of 1,920 pixels and a height of 1,080 pixels. This displays a total of 2,073,600 pixels (approximately 2.07 megapixels) on the screen. It is the standard format for modern computer monitors, televisions, and streaming platforms, featuring a widescreen 16:9 aspect ratio.

How to calculate resolution size?

To calculate the total size of a resolution in pixels, multiply its horizontal width by its vertical height. For example, to calculate the size of a 1920x1080 display, multiply 1920 × 1080 to get 2,073,600 total pixels (or approximately 2.07 Megapixels).

How to calculate resolution?

Calculating resolution parameters depends on what you need:
• Total Pixels: Multiply width in pixels by height in pixels (Width × Height).
• Aspect Ratio: Find the Greatest Common Divisor (GCD) of the width and height, then divide both dimensions by the GCD.
• Pixel Density (PPI): Calculate the diagonal resolution in pixels using the Pythagorean theorem (√(width² + height²)) and divide the result by the physical diagonal screen size in inches.

What resolution is 10,000 pixels?

In digital photography and design, a "10,000 pixels resolution" typically refers to an image size of 10,000 pixels along its longest side. The exact dimensions depend on the aspect ratio:
• 16:9 Widescreen: 10,000 × 5,625 pixels (56.25 Megapixels).
• 3:2 Photography: 10,000 × 6,667 pixels (66.67 Megapixels).
• 1:1 Square: 10,000 × 10,000 pixels (100 Megapixels).

What is the 16:9 aspect ratio in pixels?

The most common 16:9 aspect ratio resolutions are 1280×720 (HD), 1920×1080 (Full HD / 1080p), 2560×1440 (QHD / 2K), and 3840×2160 (4K UHD). Any resolution where width ÷ height ≈ 1.778 is a 16:9 format.

What is the 4:3 aspect ratio used for today?

The 4:3 aspect ratio was the broadcasting standard until HDTV adoption in the 2000s. Today it is common on iPad displays, Zoom video calls, traditional photography sensors, and legacy game titles. Typical resolutions include 800×600, 1024×768, and 1600×1200.

What resolutions does a 21:9 ultra-wide monitor use?

Common 21:9 resolutions include 2560×1080 (UW-FHD), 3440×1440 (UW-QHD), and 5120×2160 (5K ultra-wide). Use our 21:9 resolution calculator to find custom resolutions within this ratio, or to check whether source content will need letterboxing on a 21:9 display.

Why does YouTube use the 16:9 standard?

In the late 1980s, the SMPTE working group chose 16:9 as a geometric compromise between the old 4:3 TV standard and wider cinematic film formats (1.85:1 and 2.39:1). Because 16:9 sits between them, it minimises wasted space when displaying both — making it the ideal YouTube aspect ratio and global HDTV standard.

Is 1280x720 a 16:9 resolution?

Yes, 1280x720 is a standard 16:9 aspect ratio resolution. Dividing the width by the height (1280 ÷ 720) yields exactly 1.777... (or 1.78), which simplifies to the ratio of 16:9. This resolution is commonly known as High Definition (HD) or 720p.

Is 1920x1080 a 16:9 resolution?

Yes, 1920x1080 is a widescreen 16:9 resolution. When you divide the width by the height (1920 ÷ 1080), you get 1.777... (or 1.78), which translates to a standard 16:9 aspect ratio. It is the most common resolution for laptops, televisions, and online streaming services today.

What resolution is 1024x768?

A 1024x768 resolution is a standard-definition format known historically as XGA (Extended Graphics Array). It features a 4:3 aspect ratio (1024 ÷ 768 = 1.33:1) and has a total of 786,432 pixels (approx. 0.79 megapixels). While outdated for primary displays, it remains relevant in retro computing, legacy monitors, and older web layout templates.

What is "1K", "2K", and "4K" resolution?

These terms represent the approximate number of horizontal pixels in a display resolution:
• 1K: Around 1,000 horizontal pixels, typically legacy resolutions like 1024x768.
• 2K: Around 2,000 horizontal pixels. Cinema standards define 2K as 2048x1080, while in consumer electronics, 2560x1440 (QHD) is often called 2K.
• 4K: Around 4,000 horizontal pixels. In consumer TVs/monitors, this is Ultra HD (UHD) at 3840x2160 pixels, whereas DCI cinema standard is 4096x2160 pixels.

What aspect ratio does Instagram use?

Instagram supports multiple Instagram aspect ratios: 1:1 (square, 1080×1080 px) for feed posts, 4:5 (portrait, 1080×1350 px) for maximum feed real estate, 9:16 (1080×1920 px) for Reels and Stories, and 1.91:1 (landscape, 1080×566 px).

How do I calculate an LED wall resolution?

To calculate LED wall resolution: multiply the number of panels horizontally by the pixel width of one panel, and do the same vertically. For example, a 6×3 grid of P2.5 panels each at 160×160 pixels produces a wall of 960×480 pixels. Enter those values into our display resolution calculator to get the aspect ratio, total megapixels, and compatible encoder settings.

What happens if I stretch an image to a different aspect ratio?

Stretching an image to a different aspect ratio causes visible distortion — circles become ovals, people look unnaturally wide or thin. The correct alternatives are cropping (trimming edges to match the new ratio) or letterboxing / pillarboxing (adding neutral bars to fill the space without distorting content).

How do I find out the aspect ratio of my current monitor?

Open your OS display settings to find your native resolution (e.g., 1920 × 1080), then enter those values into the Ratio Finder tab of our calculator above. It will instantly reduce the resolution to its simplest ratio and show comparable standard presets.