Website Performance Audit Checklist: 5 Areas to Check

Your website might take a few seconds too long to load. It might look cramped on a phone, or feel like it belongs to a different era of your brand. Perhaps enquiries have slowly dropped and nobody can say why. Before you approve a full redesign, run a structured audit. This website performance audit checklist covers five areas, written in plain English, so you can find out what is actually wrong and spend your budget where it matters.

Why a Website Performance Audit Comes Before a Redesign

Most teams decide on a redesign because of symptoms. These are the common ones:

Slow loading, especially on mobile data
High bounce rates, where visitors leave after viewing one page
Awkward mobile layouts, such as tiny text, overlapping elements or menus that don't open properly
Falling search visibility in Google Search Console or your analytics
Fewer enquiries through forms, calls or emails

A redesign can fix some of these. It can also carry the same problems into a new, more expensive site. An audit separates cosmetic problems (dated visuals, inconsistent branding) from structural ones (heavy pages, broken indexing, fragile code). Once you know which is which, you can fund the fixes that will make a difference.

This checklist covers five areas:

Performance: speed and Core Web Vitals
Mobile: responsiveness and touch usability
UX: navigation, clarity and accessibility
SEO: the technical foundations that help you get found
Code quality: the hidden layer behind speed and stability

You can run most of these checks yourself with free tools: Google PageSpeed Insights, Lighthouse (built into Chrome DevTools) and Google Search Console. Some checks need developer access or experience, and we point those out as we go.

1. Performance Checklist: Speed and Core Web Vitals

Google measures real-world page experience with three Core Web Vitals:

LCP (Largest Contentful Paint) measures how quickly the main content appears, such as a hero image or headline. Google's "good" threshold is 2.5 seconds or less.
INP (Interaction to Next Paint) measures how quickly the page responds when someone taps, clicks or types. Good is 200 milliseconds or less.
CLS (Cumulative Layout Shift) measures how much the layout jumps around while the page loads. Good is 0.1 or less.

Enter your key pages into PageSpeed Insights: the homepage, your main service pages and your contact page. The "field data" section shows how real visitors experience the page. The "lab data" section helps you diagnose why. Google explains these metrics in its Web Vitals guidance.

Performance checklist

Total page weight: Is the page several megabytes when it could be much lighter?
Image sizes: Are images resized to the dimensions they display at, rather than uploaded straight from a camera or design file?
Image formats: Are modern formats such as WebP or AVIF used where browsers support them?
Lazy loading: Do images and videos below the fold load only when the visitor scrolls to them?
Render-blocking CSS and JavaScript: Are stylesheets and scripts delaying the first view of the page?
Unused scripts: Are old plugins, abandoned A/B tests or unused libraries still loading?
Third-party tags: How many analytics, chat, heatmap and ad scripts run on each page, and is each one still needed?
Caching: Are static files cached in the browser so repeat visits load faster?
CDN: Are assets served from a content delivery network close to your visitors, which matters if you serve several countries?
Server response time: Is the server slow to respond before anything else can load? This often points to hosting or backend issues.

Animation-heavy sites

Rich motion built with GSAP, Canvas or Three.js can make a brand memorable. Poorly built motion can also drag down load times and make scrolling feel janky. Check that heavy animation libraries load only on pages that use them, that 3D assets are compressed, and that animations stay smooth on mid-range phones as well as on a developer's laptop. Smooth playback at 60fps is achievable when the motion is built carefully. Ranbanka's work for Winning Link Business Solutions combined Three.js and GSAP with React and Next.js and delivered 60fps animations. Rich visuals and performance can coexist.

Why it matters to the business

Faster pages tend to keep visitors engaged, and Google uses page experience signals as part of how it evaluates sites. You don't need industry statistics to make the case. Compare your own bounce rates and conversion rates on fast pages against slow ones.

From our work: Ranbanka revamped the Kotak Mahindra Bank frontend, through the agency VML&YR, with pixel-perfect accuracy and enhanced interactivity. The project reported faster load times and a +40% increase in UI engagement.

2. Mobile Checklist: Responsiveness and Touch Usability

Resizing your desktop browser window is a useful first check, but it is not the same as using a real phone. Test on at least one iPhone and one Android device, plus a tablet if your audience uses them. Use mobile data rather than office Wi-Fi.

Mobile checklist

Viewport setup: Does the page scale correctly, rather than appearing as a shrunken desktop site?
Readable font sizes: Can you read body text without pinching to zoom?
Tap-target spacing: Are buttons and links large enough and far enough apart to tap accurately with a thumb?
No horizontal scroll: Does any element, such as a table, image or embed, push the page wider than the screen?
Mobile menu: Does the menu open, close and scroll easily, and can visitors reach every key page from it?
Forms: Do email fields bring up the email keyboard and phone fields the number pad? Is autofill supported?
Click-to-call and contact flows: Can a mobile visitor call, email or book with one tap?
Sticky elements: Do cookie banners, chat widgets or sticky headers cover important content on small screens?

Cross-browser and cross-device consistency

Your visitors don't all use Chrome. Check the site in Safari, Chrome, Firefox, Edge and Samsung Internet. Safari on iOS in particular can render layouts and handle animations differently.

From our work: For Mahindra Racing, through VML&YR, Ranbanka turned designs into a high-performance responsive UI that worked across all devices and reached 99% cross-browser compatibility. For Smt Kesarbai Soni Hospital, we built a patient-friendly website with clear service listings and an easy appointment contact flow optimised for mobile users. A hospital website is a good example of a site where most urgent visits happen on a phone.

3. UX Checklist: Navigation, Clarity and Accessibility

Start with a simple test. Show your homepage to someone who doesn't know your business for five seconds, then ask two questions: What does this company do? and What would you click next? If they can't answer both, you have a UX problem, however fast the page loads.

UX checklist

Clear navigation labels: Do menu items use words your customers use, rather than internal jargon?
Logical menu depth: Can visitors reach key pages within two or three clicks?
Visible calls to action: Does every important page have one obvious next step?
Consistent design: Are buttons, fonts, colours and spacing consistent from page to page?
Readable contrast: Is text easy to read against its background, including text placed over images?
Accessible forms: Does every field have a visible label, and are error messages clear?
Alt text: Do meaningful images have descriptive alternative text?
Keyboard navigation: Can you tab through the menu, links and forms without a mouse, with a visible focus outline?

Signs your site looks dated

Inconsistent branding, such as old logos, mismatched colours or several button styles
Cluttered layouts where everything competes for attention
Generic stock photography doing the work your real projects or team should do
Outdated interactions, such as auto-playing sliders, pop-ups on arrival or hover-only menus that fail on touch screens

From our work: Ranbanka rebuilt the header navigation and right-side menu for ICICI Bank, through VML&YR, to improve UX, responsiveness and interaction speed. The project reported a +35% improvement in navigation efficiency and a reduced bounce rate. For the MDG Fund, an international NGO, we developed a responsive, accessible website with a clean structure and cross-browser compatibility.

Mohit Mathur, Manager (I.T) at Sangam (India) Limited, described the value of getting UX right: "Their ability to understand our requirements and transform them into intuitive, user-friendly interfaces has significantly enhanced our client satisfaction."

4. SEO Checklist: Technical Foundations That Help You Get Found

Great content can't rank if search engines can't crawl, understand or trust your pages. Open Google Search Console and review the page indexing report (often still called the coverage report) and the page experience and Core Web Vitals reports. They show which pages are excluded from Google's index, and why.

SEO checklist

Indexability: Is your robots.txt blocking important sections? Is an XML sitemap submitted? Are any key pages accidentally set to noindex?
Title tags and meta descriptions: Is each one unique, descriptive and the right length?
One H1 per page: Does each page have a single, clear main heading?
Heading structure: Do H2s and H3s follow a logical outline?
Clean URLs: Are URLs readable and lowercase, without long strings of parameters?
Canonical tags: Are duplicate or near-duplicate pages pointing to the preferred version?
Broken links and redirects: Are there 404 errors, redirect chains or links to old domains?
Image alt text: Does alt text describe the image? This also supports accessibility.
Structured data: Is schema markup used where it is relevant, such as for organisation, local business, articles or FAQs?
HTTPS: Is the whole site served securely, with no mixed-content warnings?

Speed and mobile usability affect SEO too. The work you do in sections 1 and 2 supports your search visibility as well as your user experience.

From our work: For Shreeji Sandstone, Ranbanka created a clean, responsive website with a product showcase, contact integration and an SEO-friendly structure designed for B2B lead generation.

5. Code Quality Checklist: The Hidden Layer Behind Speed and Stability

You may never look at your site's code, but you pay for its quality every time you request a change. Clean, well-maintained code makes updates faster, safer and cheaper. Messy code makes every small edit slow and risky.

Code quality checklist

Outdated CMS, plugins or libraries: Is WordPress, or your chosen CMS, up to date? Are any plugins abandoned by their authors?
Console errors: Open Chrome DevTools and check the Console tab. Do red errors appear on key pages?
Bloated or duplicated CSS and JavaScript: Do several libraries do the same job, or is old code still shipped to every page?
Minification and bundling: Are CSS and JS files minified and bundled for production?
Security headers: Are headers such as Content-Security-Policy and Strict-Transport-Security configured?
Valid HTML: Does the markup pass a validator without major errors?
QA and testing before releases: Is every change tested across browsers and devices before it goes live?

Warning signs

Every small change seems to break something else
Developers avoid touching certain parts of the site
Simple content updates need developer time
Nobody is sure which plugins or scripts are still in use

From our work: Ranbanka has provided ongoing frontend support for IDFC First Bank, using GSAP animations, jQuery, SCSS and Gulp while maintaining enterprise-grade performance standards. The result is 50+ features shipped with zero production bugs. That is what disciplined code and testing look like in day-to-day practice.

Sonal Rathi, Client Solution Manager at VMLY&R, said: "Ranbanka Systems excels in frontend development, delivering responsive, user-friendly interfaces that elevate user experience. Their attention to detail, creativity, and timely delivery impressed us."

Prioritise Your Fixes and Get a Free Website Performance Audit

Once you've worked through the checklist, sort your findings into two groups.

Quick wins usually take hours or days:

Compressing and resizing images
Removing unused scripts, plugins and third-party tags
Fixing broken links and missing title tags or meta descriptions
Adding alt text and form labels
Updating your CMS and plugins

Structural fixes need planning and budget:

Rebuilding a slow theme or legacy codebase
Redesigning navigation and information architecture
Moving to better hosting, adding a CDN or reworking backend performance
Rebuilding animation-heavy sections so they perform well

Start with the quick wins on your highest-traffic and highest-converting pages. Then measure the results before you commit to bigger work.

Copyable one-page checklist

Performance

LCP, INP and CLS within Google's "good" thresholds
Images resized, compressed and served as WebP or AVIF
Lazy loading below the fold
No render-blocking or unused CSS and JS
Third-party tags reviewed
Caching, CDN and fast server response in place

Mobile

Tested on real iOS and Android devices
Readable text, well-spaced tap targets, no horizontal scroll
Mobile menu, forms and click-to-call work
Consistent in Safari, Chrome, Firefox, Edge and Samsung Internet

Five-second clarity test passed
Clear labels, shallow menus, visible CTAs
Consistent design and readable contrast
Accessible forms, alt text and keyboard navigation

SEO

Robots.txt, sitemap and noindex checked
Unique titles and meta descriptions, one H1 per page
Clean URLs, canonical tags, no broken links
Structured data and HTTPS in place

Code quality

CMS, plugins and libraries up to date
No console errors
Minified, bundled, de-duplicated assets
Security headers and valid HTML
QA process before every release

When DIY stops being enough

A checklist tells you what is wrong. It doesn't always tell you why, or how to fix it safely. It may be time to bring in a development team if:

The same issues keep returning after you fix them
Your site runs on custom code or a heavily modified theme
Your team doesn't have the time to investigate and test fixes properly

Ranbanka Systems offers a free website performance audit. We respond within 24 hours, work under NDA and confidentiality, and offer a free initial consultation to talk through what we find. Founded in 2020 in Udaipur, India, we have delivered 50+ projects for clients in India, the USA, the UK and worldwide. Our work covers web development, UI/UX design, QA and testing, and maintenance and support.

If you'd like to see our work first, browse the portfolio, review our services, see who we've worked with on the clients page, or read more about Ranbanka Systems. For more practical guides, visit the blog.

Ready to find out what's holding your site back? Request your free website performance audit or book a free consultation today.