CSS Media Query Range Tester â Online Width/Height Debug
Paste media queries and see a visual indicator of which rules apply at current viewport size.
UD5 Toolkit
Online Verify Breakpoint Conditions â Test your responsive design rules directly in the browser
Quick Presets:
Enter a media query and press Test
Resize your browser window to see updates
xs: <576pxsm: â„576pxmd: â„768pxlg: â„992pxxl: â„1200pxxxl: â„1400pxprint, screen, or any combination. The browserâs matchMedia() API will evaluate the whole media query string exactly as you wrote it, including media types.
and instead of ,), or forgetting that media queries are caseâsensitive for feature names. Always validate with this tool and check your CSS syntax.
Paste media queries and see a visual indicator of which rules apply at current viewport size.
Write a media query and see if it matches as you resize the iframe. Understand width, height, and resolution queries.
Paste a media query and instantly check for syntax errors. See if it's correctly formed. Quick developer tool.
Build a CSS media query by selecting feature, operator, and value. Copy the exact syntax for your stylesheet.
Experiment with CSS container queries in a live editor. Resize the container and see styles change based on its width/height. Learn modern responsive.
Test the new style() function inside @container to query custom property values. Revolutionary componentâbased responsive design.
Combine aspectâratio with minâ/maxâwidth/height and see how the box responds. Understand sizing constraints. Copy the pattern.
Simulate reduced motion preference and test your animations. Copy the media query snippet. Keep your users safe.
Upload one image at multiple widths and generate the complete img srcset and sizes attributes. Perfect for performance.
Enter a website URL and apply a protanopia/deuteranopia/tritanopia filter. Test full page accessibility.
Compare breakâall, keepâall, and overflowâwrap: anywhere/breakâword. Paste long words and see how they wrap.
Enter foreground and background colors to instantly see the contrast ratio and pass/fail for AA and AAA. Simple and fast.
Drag a virtual ruler across your screen to measure pixel distances. Horizontal and vertical guides. Useful for UI designers checking alignment.
Wrap text around an irregular shape and adjust the margin and alpha threshold. Magazines layout on the web.
Detect your current screen resolution, viewport dimensions, and device pixel ratio. Useful for responsive design testing. No data collection.
Upload an image at multiple widths and generate a complete <picture> or <img srcset> snippet. Modern web performance.
Open a test video in PictureâinâPicture mode. Control entering and leaving PiP. Copy the code snippet for your own app.
Experiment with the CSS color-mix() function. Pick two colors and mix them in different color spaces (srgb, oklch). Copy the CSS.
Place a table caption on top, bottom, or inlineâstart/end. See the live change. Copy the code.
Toggle between light and dark mode for a demo page. See how to use the media query. Copy the pattern.
Upload multiple sizes of the same image and generate the complete srcset and sizes attributes. For perfect responsive performance.
Display your screen's current devicePixelRatio. See how it changes when you zoom. Useful for highâres image decisions.
Apply a convolution filter (blur, sharpen) using a Web Worker. See the UI stay responsive while processing. Learn multithreading in the browser.
See how your title and meta description will be truncated in Google SERP by pixel width. Optimize clickâthrough.
Browse the OKLCH color space with sliders for lightness, chroma, and hue. See the CSS oklch() code. Modern and accessible.
Upload two images and see a diff overlay highlighting the pixel differences. Adjust tolerance. For regression testing.
Start from a base color and use `oklch(from color l c h)` to create lighter or darker variants. Copy the code.
Create a responsive box that maintains a specific aspect ratio using the aspectâratio property. Copy the simple CSS.
Toggle imageârendering: auto, pixelated, crispâedges on a scaled image. Essential for pixel art display.
Enter the URL of any online image and extract its dominant colors or pick colors with a magnifier. No upload, crossâorigin friendly.