What we check and why

Visitors judge a site in the first few seconds. Slow first impressions increase bounce rates and weaken Google rankings.

Threshold

Flagged above 2.5s. Critical above 4s.

Source

Largest Contentful Paint (Lighthouse, mobile)

Fix

Compress and properly size the hero image, preload it, and remove anything that blocks the page from rendering first.

Jumping content causes mis-taps and makes a site feel unreliable, which hurts trust and conversions.

Threshold

Flagged above 0.1. High above 0.25.

Source

Cumulative Layout Shift (Lighthouse, mobile)

Fix

Set width and height on images and embeds, reserve space for banners and ads, and avoid inserting content above what’s already visible.

Laggy buttons and menus feel broken. Visitors give up on forms and checkouts that don’t respond straight away.

Threshold

INP above 200ms or TBT above 200ms. High above 500ms INP or 600ms TBT.

Source

Interaction to Next Paint (real-user data), or Total Blocking Time as a proxy

Fix

Cut or defer non-essential scripts (chat widgets, trackers, sliders), split large bundles, and load third-party code after the page is interactive.

Visitors stare at a blank screen for longer, and many leave before the page shows up.

Threshold

Flagged when Lighthouse estimates any saving. High above 1s.

Source

render-blocking-resources

Fix

Inline the small amount of CSS needed for the first screen, and add defer or async to scripts that aren’t needed immediately.

Every extra kilobyte costs load time and data on mobile, and delays when visitors can actually use the page.

Threshold

Flagged above 20 KB of unused code. High above 150 KB.

Source

unused-javascript

Fix

Remove unused plugins and libraries, load scripts only on the pages that need them, and enable code splitting.

Extra stylesheet weight delays the first render, especially on slower mobile connections.

Threshold

Flagged above 20 KB of unused styles.

Source

unused-css-rules

Fix

Remove unused theme and plugin styles, and purge unused CSS as part of the build.

Oversized images are the most common reason small-business sites feel slow on phones.

Threshold

Flagged above 50 KB of possible savings. High above 500 KB.

Source

uses-optimized-images, modern-image-formats, uses-responsive-images

Fix

Export images at the size they’re displayed, convert them to WebP or AVIF, and serve smaller versions to mobile screens.

Repeat visitors, often your warmest leads, get a slower experience than they should.

Threshold

Flagged when static files have short cache lifetimes.

Source

uses-long-cache-ttl

Fix

Set long Cache-Control lifetimes (for example one year) on images, fonts, CSS and JavaScript, using versioned file names.

Uncompressed files load noticeably slower on mobile data, for no benefit.

Threshold

Flagged when compression would save any bytes.

Source

uses-text-compression

Fix

Enable Gzip or Brotli compression on your server or CDN. It’s usually a single setting.

Without a title, search engines guess what to show, and fewer people click through to your site.

Threshold

Flagged when the page has no <title> element.

Source

document-title

Fix

Add a unique title of around 50 to 60 characters that includes your main service and location.

A clear, persuasive description improves click-through from Google at no cost.

Threshold

Flagged when there is no meta description.

Source

meta-description

Fix

Write a 140 to 160 character description that says what you do, who it’s for, and why to choose you.

Headings help search engines and screen readers understand the page. A missing or muddled H1 weakens both.

Threshold

Flagged when there is no H1 (high) or more than one H1 (low).

Source

HTML check of the page

Fix

Use a single H1 for the main headline, and H2/H3 for sections below it.

Structured data can unlock richer search listings, like star ratings and business details, which get more clicks.

Threshold

Flagged when no structured data is present.

Source

HTML check for JSON-LD or schema.org markup

Fix

Add LocalBusiness or Organization JSON-LD with your name, address, phone, hours and logo.

A sitemap helps Google find and index all your pages, especially new or deeper ones.

Threshold

Flagged when /sitemap.xml is missing or invalid.

Source

HTML check of /sitemap.xml

Fix

Generate an XML sitemap (most CMSs and SEO plugins do this), then submit it in Google Search Console.

A broken robots.txt can accidentally stop Google from crawling important pages.

Threshold

Flagged when robots.txt is invalid.

Source

robots-txt

Fix

Fix the syntax errors in robots.txt and reference your sitemap from it.

Visitors using assistive technology miss key content, and you lose an easy source of image search traffic.

Threshold

Flagged for any image without alt text. High for 5 or more.

Source

image-alt

Fix

Add short, descriptive alt text to meaningful images, and empty alt="" to purely decorative ones.

Low-contrast text is hard to read in sunlight and for older visitors, which quietly costs you enquiries.

Threshold

Flagged for any text below WCAG AA contrast.

Source

color-contrast

Fix

Darken light grey text or lighten backgrounds so text meets a 4.5:1 contrast ratio.

Unlabelled fields make contact and booking forms harder to complete, and some visitors can’t complete them at all.

Threshold

Flagged for any form field without a label.

Source

label

Fix

Give every input a visible <label> connected to it, not just placeholder text.

Screen-reader users hear “link” with no context, and search engines get weaker signals.

Threshold

Flagged for any link without readable text.

Source

link-name

Fix

Add descriptive text or an aria-label to icon links (social icons, logos, arrows).

Without visible focus, keyboard users get lost and can’t complete forms or bookings.

Threshold

Checked by hand during a full review. Not included in automated reports.

Source

Manual review

Fix

Keep or add a clear focus outline on all links, buttons and form fields.

Security warnings scare away visitors instantly, and Google ranks secure sites higher.

Threshold

Flagged when the page or any of its resources load over plain HTTP.

Source

is-on-https

Fix

Install an SSL certificate, redirect all HTTP traffic to HTTPS, and update any http:// links to images and scripts.

Most small-business traffic is mobile. A non-mobile-friendly page loses those visitors and ranks lower.

Threshold

Flagged when the mobile viewport tag is missing or incorrect.

Source

viewport

Fix

Add <meta name="viewport" content="width=device-width, initial-scale=1"> and check the layout on a phone.

Script errors can silently break forms, tracking, and interactive features without anyone noticing.

Threshold

Flagged for any error in the browser console.

Source

errors-in-console

Fix

Open the browser developer console, fix or remove the failing scripts, and re-test key forms.