Best alternatives to Responsive Website Testing Toolkit - Multiple Viewport Simulator (2026)

Responsive Website Testing Toolkit - Multiple Viewport Simulator today

Responsive Website Testing Toolkit alternatives, compared

1. 1

   Mobile Simulator – Responsive Testing Tool

   Phone Simulator – Free Chrome Extension to test and preview your site on 80+ devices.

   ≈1M users4.9★ from 5.3K ratingsUpdated 4 days ago13 permissions

   • About 167× more users than Responsive Website Testing Toolkit
   • Rated 0.9 stars higher
   • Updated more recently
   • Asks for more permissions (13 vs 6)

   Mobile Simulator alternativesCompare side by side
2. 2

   Responsive Tester

   Test responsive web designs or mobile pages and see if it is mobile friendly

   ≈40K users3.0★ from 95 ratingsNot updated for 2+ years1 permissions

   • About 6.7× more users than Responsive Website Testing Toolkit
   • Rated 1.0 stars lower
   • Updated less recently
   • Asks for fewer permissions (1 vs 6)
   • Listed under Workflow & Planning

   Responsive Tester alternativesCompare side by side
3. 3

   Viewport Resizer: Ultimate Device Emulator & Website Testing Tool

   Emulate devices, resize screens, and perfect your web design effortlessly with this cutting-edge testing and presentation tool.

   ≈80K users4.1★ from 287 ratingsUpdated 11 months ago5 permissions

   • About 13× more users than Responsive Website Testing Toolkit
   • Updated less recently
   • Asks for fewer permissions (5 vs 6)

   Viewport Resizer alternativesCompare side by side
4. 4

   Website Responsiveness Checker

   Optimize your website for all devices with website responsiveness checker

   ≈4K users3.8★ from 4 ratingsNot updated for 3+ years1 permissions

   • About 1.5× fewer users than Responsive Website Testing Toolkit
   • Updated less recently
   • Asks for fewer permissions (1 vs 6)

   Website Responsiveness Checker alternativesCompare side by side
5. 5

   Marker.io: Visual bug reporting for websites

   Report visual bugs directly into your favorite tools, without leaving your website or web app

   ≈30K users4.2★ from 171 ratingsUpdated 6 months ago8 permissions

   • About 5.0× more users than Responsive Website Testing Toolkit
   • Asks for more permissions (8 vs 6)

   Marker.io alternativesCompare side by side
6. 6

   Responsive Viewer

   Show multiple screens once, Responsive design tester

   ≈400K users4.2★ from 352 ratingsUpdated 3 months ago6 permissions

   • About 67× more users than Responsive Website Testing Toolkit
   • Updated more recently

   Responsive Viewer alternativesCompare side by side
7. 7

   Heurio - Website Review, Heuristic Evaluation & Vibe Coding Feedback

   Fastest website review, bug report and heuristic evaluation tool for designers and devs.

   ≈10K users4.7★ from 74 ratingsUpdated 3 months ago4 permissions

   • About 1.7× more users than Responsive Website Testing Toolkit
   • Rated 0.7 stars higher
   • Updated more recently
   • Asks for fewer permissions (4 vs 6)

   Heurio alternativesCompare side by side
8. 8

   Mobile View: Test responsive designs fast

   Test your responsive designs on multiple devices at once.

   ≈20K users4.2★ from 40 ratingsNot updated for 2+ years7 permissions

   • About 3.3× more users than Responsive Website Testing Toolkit
   • Updated less recently
   • Asks for more permissions (7 vs 6)

   Mobile View alternativesCompare side by side
9. 9

   Silktide - website accessibility simulator

   A browser plugin that helps you develop accessible websites by simulating a range of experiences.

   ≈10K users4.0★ from 15 ratingsNot updated for 2+ years3 permissions

   • About 1.7× more users than Responsive Website Testing Toolkit
   • Updated less recently
   • Asks for fewer permissions (3 vs 6)
   • Listed under Accessibility

   Silktide alternativesCompare side by side
10. 10

    LoadFocus - JMeter Cloud Load Testing & Website Performance

    Record JMeter tests while browsing, upload JMX files to the cloud, and run load tests with thousands of users.

    ≈1K users5.0★ from 1 ratingUpdated 5 months ago5 permissions

    • About 6.0× fewer users than Responsive Website Testing Toolkit
    • Asks for fewer permissions (5 vs 6)

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Responsive Website Testing Toolkit alternatives: questions

Users and ratings are the figures shown on the Chrome Web Store, re-checked continuously. Alternatives are matched on name, description, category and topic. Browse best-of lists by niche.