Rulers & Screen

Pixel Ruler — Measure Pixels, Coordinates & CSS Dimensions Online

Measure screen pixels, (X, Y) coordinates, bounding box width and height, diagonal distance, and CSS dimensions with a multi-edge virtual on-screen ruler and clipboard screenshot paste.

TL;DR: Pixel Ruler is a 100% free client-side measurement utility. Calibrate scale with reference objects, inspect dimensions, and measure angles or areas with zero file uploads and zero telemetry.

Pixel Ruler
PPI: 96.0
Measurements: 0
Click and drag on ruler board to measure

Screen Calibration (1:1 Actual Size)

Hold your physical card or object against the screen. Drag the slider or click ± until the purple outline matches your physical object with 100% accuracy.

96.0
Place standard credit card here
(85.60 mm × 53.98 mm)

How to Use Online Ruler Suite

1. Ruler Edges & Highlight Ticks: As you move your mouse or touch the canvas, high-contrast pointer chips on all 4 ruler tracks highlight the exact measurement at the tick marks.

2. Pinpoint Measurement Marks: Click anywhere directly on the ruler tracks (or select the Pin tool) to drop persistent measurement pins. Copy or clear them from the pin chips bar.

3. Sliding Caliper Mode: Switch to Caliper tool to drag two sliding jaws across the screen, perfect for measuring coins, keys, or screws pressed flat against your monitor or phone glass.

4. Device Calibration Presets: Select your phone (iPhone, Galaxy, Pixel), laptop (MacBook, Windows), or monitor from the top dropdown, or click Auto-Detect for instant true-to-life 1:1 scale.

5. Snap-to-Tick & Fractions: Toggle Snap () to snap measurements to precise millimeters or sixteenths of an inch. Toggle ½ Frac to view fractional inches.

Understanding Pixel Ruler

Measure screen pixels, (X, Y) coordinates, bounding box width and height, diagonal distance, and CSS dimensions with a multi-edge virtual on-screen ruler and clipboard screenshot paste. Designed for architects, web designers, engineers, students, and homeowners who need instant, high-precision dimensional analysis directly in their web browser without installing heavy software or paying subscription fees.

Mathematical Formula & Technical Methodology

\Delta x = |x_2 - x_1|, \quad \Delta y = |y_2 - y_1|, \quad d = \sqrt{\Delta x^2 + \Delta y^2}

Formula Variables Explained:
Calculates horizontal distance, vertical distance, and Euclidean diagonal pixel distance between cursor points on the native bitmap raster.

Step-by-Step Worked Example

Measuring a design button from (120, 80) to (360, 130) yields width: 240px, height: 50px, and diagonal distance: sqrt(240^2 + 50^2) = 245.15px.

Direct Answer: Pixel Ruler Overview

Quick Answer: The Pixel Ruler allows web developers, UI/UX designers, and digital creators to inspect exact pixel distances, bounding boxes, and (X, Y) bitmap coordinates on any screen or uploaded graphic. Drag across any region to inspect width, height, diagonal pixels, and ready-to-copy CSS rules in real time.

Connected Measurement Guides & Tools

100% Client-Side Privacy Guarantee

All image rendering, camera streaming, coordinate mapping, and mathematical calculations execute locally inside your web browser using HTML5 Canvas 2D and sub-pixel JavaScript algorithms. Zero files or camera feeds are ever sent to remote servers.

Frequently Asked Questions

Upload an image or paste a screenshot directly into the Pixel Ruler (Ctrl+V / Cmd+V). Click and drag across any region to inspect width, height, diagonal pixel distance, and bounding box coordinates in real time.
Paste or upload your graphic onto the canvas. Use the Box mode to drag over the image or element edges; the HUD displays width and height in exact CSS pixels.
Press PrintScreen (or Cmd+Shift+4 on Mac) to capture your screen, paste it into the Pixel Ruler with Ctrl+V, and drag across any section to read dimensions, aspect ratios, and coordinate offsets.
Pixel rulers are used by web developers, UI/UX designers, and graphic artists to measure element padding, margins, button dimensions, banner aspect ratios, image pixel sizes, and CSS layout grids.
Yes. When you measure an element with the box tool, the live readout displays CSS declaration snippets (e.g. width: 320px; height: 48px; aspect-ratio: 20/3) ready to copy directly into your stylesheet.
In Word Online, navigate to the "View" tab on the ribbon and check the "Ruler" box. For exact pixel measurements of document elements or tables, take a screenshot and paste it into this Pixel Ruler.
In PowerPoint Online, click "View" in the top menu and check "Ruler". You can also enable "Gridlines" to assist with slide element alignment.
Yes. Use the edge mode buttons on the toolbar to toggle between a 4-sides box frame ruler, dual horizontal rulers, dual vertical rulers, or a single top ruler.

Embed This Tool

Add the live Pixel Ruler to your own website with this embed code:

<iframe src="https://nexlove.org/embed/pixel-ruler.html" width="100%" height="650" style="border:1px solid #e2e8f0;border-radius:12px" title="Pixel Ruler — NexLove" loading="lazy"></iframe>

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