Viewpo
Viewpo vs Screenfly & Free Responsive Checkers
Free online responsive design testing tools
Responsive checker that actually works — real browser rendering, not broken iframes
Feature Comparison
How Viewpo and Screenfly & Free Responsive Checkers compare across key capabilities.
Works on all sites
Viewpo
Screenfly & Free Responsive Checkers
Real browser rendering
Viewpo
Screenfly & Free Responsive Checkers
A-F responsive grade
Viewpo
Screenfly & Free Responsive Checkers
Automated auditing
Viewpo
Screenfly & Free Responsive Checkers
Shareable reports
Viewpo
Screenfly & Free Responsive Checkers
HTTP API
Viewpo
Screenfly & Free Responsive Checkers
No account required
Viewpo
Screenfly & Free Responsive Checkers
Ad-free
Viewpo
Screenfly & Free Responsive Checkers
Price
Viewpo
Screenfly & Free Responsive Checkers
| Feature | Viewpo | Screenfly & Free Responsive Checkers |
|---|---|---|
| Works on all sites | Often fails (iframe) | |
| Real browser rendering | ||
| A-F responsive grade | ||
| Automated auditing | ||
| Shareable reports | ||
| HTTP API | ||
| No account required | ||
| Ad-free | ||
| Price | Free (50 audits/mo) | Free (ad-supported) |
Where Viewpo wins
Key advantages Viewpo has over Screenfly & Free Responsive Checkers.
Real browser rendering (Chromium) — not iframes. Works on every site
Automated audit with A-F grading — not just visual inspection
Shareable, professional reports — link-based with OG preview cards
API access for AI agents and CI/CD
Modern, ad-free UI
Actually works on sites that block iframes (which is most of them)
Where Screenfly & Free Responsive Checkers wins
An honest comparison. Here's where they have the edge.
Zero friction — paste a URL and see results
No account required
Multiple preset screen sizes
Some offer device mockup frames
Frequently Asked Questions
Common questions about Viewpo vs Screenfly & Free Responsive Checkers.
Most free responsive checkers use iframes to display your site at different sizes. Modern websites set X-Frame-Options or Content-Security-Policy headers that block iframe embedding — so you see a blank page or an error. Viewpo uses a real Chromium browser to render your site, which works regardless of iframe restrictions.
Try Viewpo free — no install required
Paste any URL and get a responsive design audit with screenshots and an A-F grade. 50 free audits per month.
Free during beta. Plans from $19/mo at launch — early supporters get a lifetime discount.