Yes. The free tier includes 50 audits per month at 3 viewport sizes with shareable reports. No credit card required. Pro ($19/mo) and Team ($49/mo) plans add more viewports, batch audits, and team features.

How is this different from Chrome DevTools?

Chrome DevTools simulates one viewport at a time and requires manual inspection. Viewpo shows your site at multiple viewports simultaneously, runs automated responsive checks, gives you a grade, and generates a shareable report — all in seconds.

Does Viewpo work with sites that block iframes?

Yes. Most free responsive checkers use iframes, which fail on sites with X-Frame-Options or CSP headers. Viewpo uses a real Chromium browser, so it works on every site regardless of iframe restrictions.

Can AI agents use Viewpo?

Yes. AI coding agents can call the Viewpo API to audit their own output. Write CSS → call Viewpo → see overflow issues → fix → re-audit → Grade A. It closes the visual feedback loop that no AI tool has natively.

Yes. Viewpo never stores your site content. Screenshots are cached temporarily for report sharing, then deleted. Viewpo uses privacy-first Plausible analytics with no cookies.

Coming soon — register for early access

Is your site actually responsive?

Real browser screenshots at phone, tablet, and desktop. Automated checks for overflow, touch targets, contrast, and accessibility. A-F grade with specific fixes. No install required.

Free tier included · No credit card required · Real Chromium rendering

Sample Audit

See what an audit looks like

Every audit gives you real browser screenshots, an A-F grade, and specific issues to fix — in plain language.

Grade B — Good

example.com · 2 minor issues found

Audited 12 seconds ago

Phone

375px

Tablet

768px

Laptop

1280px

Desktop

1920px

Issues found

Navigation overflows on phone

The navigation menu is wider than the screen at 375px — visitors would need to scroll sideways.

Phone (375px)

3 buttons too small to tap

Three CTA buttons are smaller than 44×44px on mobile. Visitors may struggle to tap them accurately.

Phone (375px)

Sample audit preview — your results will show real screenshots of your site

Built by developers

For everyone who builds for the web — whether you write CSS or your AI does.

Real browser rendering on Cloudflare's global network. Not iframes.

Privacy-first

Viewpo never stores your site content. Screenshots are cached for sharing, then deleted.

Real browser audits

Screenshots rendered in real Chromium at actual viewport sizes — not simulated previews.

How It Works

How to audit your site's responsive design

Paste your URL

Any deployed site, preview deploy, or localhost tunnel. If it has a URL, Viewpo can audit it.

Pick your viewports

Phone, tablet, laptop, desktop — or set custom sizes. Viewpo renders your site at each one using a real browser.

Get your grade

A-F score with specific issues and screenshots at every size. Share the report link or fix what's broken.

Features

Everything you need to ship responsive

Viewpo doesn't just show you viewports — it tells you what's broken and how to fix it.

Multi-Viewport Screenshots

See Your Site at Every Screen Size

Real browser screenshots at 4 sizes — phone (375px), tablet (820px), laptop (1440px), and desktop (1920px). See exactly what your visitors see at every breakpoint.

A–F Responsive Grade

One Clear Answer

Automated audit runs 5+ checks across every viewport. Results scored from A (excellent) to F (broken). A single, clear answer you can share with clients or teammates.

Plain-Language Explanations

Understand Every Issue

“This element is wider than the screen on mobile — visitors would need to scroll sideways.” Not “overflow detected on `.hero-container`.” You don’t need CSS knowledge.

Shareable Report Links

Replace Screenshots with Links

Every audit generates a unique, shareable URL. Anyone can view it without signing up. Replace “let me take some screenshots” with “here’s the report link.”

Real Browser Rendering

Not Iframes — Actually Works

Viewpo uses a real Chromium browser to render your site. Not an iframe. Works on every site, including those that block embedding.

HTTP API

For AI Agents & Automation

JSON API that any tool can call. Send a URL, get back screenshots + audit results + grade. Works with Claude Code, Cursor, GitHub Actions, or any HTTP client.

Who It's For

Built for everyone who builds for the web

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For Vibe-Coders

Built with AI? Check if it works on phones.

Paste the URL into Viewpo, get your grade in seconds, fix the overflow issues it found, re-audit, and share the A-grade report with your client.

Explore for vibe-coders

For Designers

Share a report link, not a screenshot.

See all viewports at once. The padding is wrong at 375px — share the report link in Slack with one click. No annotation needed.

Explore for designers

$ viewpo audit

Grade: B (87/100)

2 issues found

For Developers

Add responsive audits to your CI pipeline.

Every PR preview deploy gets audited automatically. Grade below B? The check fails. No more "it looked fine on my monitor" bugs.

Explore for developers

API

D → A

For AI Agents

Close the visual feedback loop.

Your AI calls the Viewpo API, gets Grade D with 7 overflow issues, fixes the CSS, re-audits, gets Grade A. Fully automated.

Explore for ai agents

What Viewpo Checks

5 automated checks. More coming.

Every audit runs these checks across all viewports and explains issues in plain English.

Overflow

Elements wider than the screen

Causes horizontal scrolling on phones — visitors can't see your content

Touch Targets

Buttons and links too small to tap

Visitors can't click things on mobile — frustrating and inaccessible

Images

Missing alt text, oversized images, no lazy loading

Slow load times, broken accessibility, wasted bandwidth

Contrast

Text that's hard to read against its background

Fails accessibility standards, loses visitors with visual impairments

Accessibility

Missing landmarks, broken heading order, unlabelled inputs

Screen readers can't navigate your site, fails WCAG compliance

Coming soon

Core Web Vitals

LCP, CLS, INP per viewport

SEO & Social Preview

OG tags, Twitter cards, JS rendering gap

Design Token Compliance

Brand consistency checking

Interactive Sessions

Live AI agent interaction with your site

Pricing

Start free. Upgrade when you need more.

No credit card required. No install. Just paste a URL.

Free

$0 forever

Perfect for trying Viewpo on your projects.

50 audits/month
3 viewports
Shareable reports
Basic API

Pro

$19 /month

For builders who ship regularly.

500 audits/month
6 viewports
Full API access
Batch 5 URLs

Team

$49 /month

For teams with CI/CD and quality gates.

2,000 audits/month
Custom viewports
GitHub Action
10 seats

See full comparison →

Free Developer Tools

Free tools for responsive design. No sign-up required.

My Viewport

What screen size is this?

Device Viewport Database

Every device, every viewport.

Breakpoint Visualiser

See where devices land.

View all tools

Frequently Asked Questions

Quick answers to help you decide.

Viewpo is a web-based responsive design auditor. Paste any URL, see real browser screenshots at phone, tablet, laptop, and desktop sizes, and get an A–F grade with specific issues to fix. No install required.

Find out in seconds — paste a URL and get your grade

Find out in seconds. Paste a URL, get real browser screenshots at every screen size, and an A-F grade with specific issues to fix.

Free during early access. Pro plans from $19/mo — early supporters get a lifetime discount.