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CLUSTER WEB-WEBSITE-DESIGN · 16 ENTRIES · EARLIEST ENTRY 2026-10-08

Device screen simulation for responsive testing

This cluster comprises web-based tools that simulate device screens—such as mobile phones, desktops, and tiny computers—to help developers preview and test responsive web design. The dated history is too thin to read a shape from, with only one entry having a source date and six members undated, suggesting the cluster predates the index or lacks reliable dating. Traction leaders include Desktop Browser • Zoomable, Cell Phone Simulator, and Device Simulator & Tester: Unleash Real Time Device Experience, all with zero stars but ranked by activity signal.

Entry timeline

ENTRY TIMELINE

DEC 2017: 1MAY 2021: 1SEP 2022: 1AUG 2024: 1AUG 2026: 8SEP 2026: 3OCT 2026: 1
DEC 2017OCT 2026

Each bar is the month a member carries, which is a creation date where the source published one and a crawl date otherwise. Nothing in the index was found before 11 August 2026, and coverage broadened sharply on 14–15 August, so a bar from then on reports how much we found that month, not how much was built; an earlier bar reports how far back a member's own source dated it — not how long we have been watching.

Members by activity

Activity signals, not revenue.

Build origin · 3 ai-built · 2 hand-coded · 11 unlabelled

Operator · 3 hobby · 1 commercial · 2 open source · 10 unlabelled

Two labels per entry, never collapsed into one: how it was built, and who stands behind it. Counted over the 16 listed below. Unlabelled means nothing has decided yet — not that the answer is small.

  1. 01viewport-lab2★6 daysliveBrowser extension that provides a workspace for reviewing and QA-testing responsive web pages across multiple device viewport sizes.
  2. 02Codable0★1 moliveMobile web developer toolkit with Safari inspection tools, responsive resizing, and a JavaScript scratchpad for testing websites on iPhone and iPad.
  3. 03Desktop Browser • Zoomable0★6 mostalelivecommercialProvides a mobile browser that simulates a desktop screen for viewing full desktop versions of websites.
  4. 04Dippi0★7 mostalelivehand-codedopen sourceCalculator tool that determines a display's DPI, aspect ratio, and pixel density classification from its screen size and resolution, aiding hardware purchase decisions.
  5. 05PX:VW - converter0★4 yrabandonedlivehand-codedopen sourceUnit converter app that converts pixel values to viewport units for responsive web design.
  6. 06Dippi0★unknownliveDisplay utility that calculates DPI and aspect ratio from a screen's size and resolution and advises whether the display is HiDPI-ready.
  7. 07My screen size0★unknownlivehobbyWeb utility that displays a visitor's browser, operating system, and window dimensions in real time.
  8. 08Device Simulator & Tester: Unleash Real Time Device Experience0★unknownliveWeb app that simulates multiple device screens at once so developers can preview and test website responsiveness live.
  9. 09youtubethumbnailpreview.vercel.app0★unknownliveWeb tool that previews YouTube video thumbnails and shows how they appear at different display sizes.
  10. 10DeviceSnapshot0★unknownliveai-builtWeb tool that displays a website on multiple device screens at once for responsive design testing.
  11. 11iPhone Sizer0★unknownliveai-builtWeb tool that displays iPhone screen dimensions and sizes to help with design and layout decisions.
  12. 12Device Width | Sahil Rajput0★unknownlivehobbyWeb tool that displays the current width of the user's screen in pixels to assist responsive design.
  13. 13goodmax - Global Website Testing Platform0★unknownliveai-builtCross-browser and real-device website testing platform for developers.
  14. 14What Is My Screen Resolution? - Free Screen Size Checker0★unknownliveWeb tool that reports the visitor's screen resolution, viewport size, pixel density, color depth, and pixel ratio.
  15. 15Tinybrowse0★unknownliveA web tool that displays a website in a simulated tiny computer or phone screen for responsive design testing.
  16. 16Blackscreen – click anywhere to go fullscreen0★unknownlivehobbyWeb tool that turns the display black and enters fullscreen mode when the screen is clicked.

Ranked by traction, highest first, and paged 20 at a time — this is a window on the cluster, never the whole of it. Ties are broken by a stable id so a product cannot appear on two pages or fall between them. Browse every cluster.