Speed & Core Web Vitals
A faster WordPress site, proven in real-user data.
WordPress speed optimization, measured properly: we find what actually slows your pages down — hosting, images, plugins, scripts — fix it on staging, and show you the before-and-after in Google’s own field data.
Field + lab report
Staging first
Your theme stays
- LCP Good 1.7 s
- INP Good 120 ms
- CLS Good 0.02
Example report for illustration — your audit shows your real numbers.
The state of WordPress speed
Fewer than half of WordPress sites pass Core Web Vitals on mobile.
The 2025 Web Almanac puts WordPress at 45% — behind Wix and Squarespace at 74%. Its authors are clear about why: themes, plugins and configuration matter more than the platform. That’s good news, because WordPress speed optimization can fix all three.
2.9 MB
median weight of a WordPress mobile page (2,894 KB) — about 900 KB of it images
The three metrics
What Google actually measures.
Core Web Vitals are scored on the 75th percentile of real visits, split by mobile and desktop — so three out of four visitors need a good experience. Pick a metric and drag the marker to see how Google rates it.
Drag to see how Google rates a value.
How long until the largest element on screen — usually the hero image or headline — has rendered. It is the closest number to “when does this page look ready?”
What moves it on WordPress
- Faster server response and full-page caching
- Preloading and correctly sizing the hero image
- Removing render-blocking CSS and JavaScript
Drag to see how Google rates a value.
How quickly the page responds when someone taps, clicks or types, judged across the whole visit. Heavy plugin JavaScript is the usual culprit on WordPress.
What moves it on WordPress
- Removing or deferring unused plugin scripts
- Breaking up long JavaScript tasks
- Delaying chat widgets, ads and trackers until they are needed
Drag to see how Google rates a value.
How much the layout jumps while it loads — the reason people tap the wrong link. Unsized images, late ads and web fonts cause most of it.
What moves it on WordPress
- Width and height on every image and embed
- Reserved space for ad slots and banners
- Font loading that doesn’t reflow text
Source: web.dev — Web Vitals
Measure first
We start with what your visitors experience.
A Lighthouse score is one test on one machine. Google ranks on field data from real Chrome users, so that’s the baseline for our WordPress speed optimization — and the finish line.
- Field data from Chrome usersYour 28-day Chrome UX Report numbers for mobile and desktop, recorded before we touch anything.
- Lab tests on every key templateHome, posts, archives, product and checkout pages — each traced to the exact resources slowing it down.
- A written diagnosisWhat is slow, why, what we’ll change and what it should be worth — before you approve the work.
Inside a slow page load
Where the 2.5 seconds should go.
Google splits LCP into four parts and suggests a budget for each. On a slow WordPress site one part is usually far over budget — that’s where we start. Select a segment to see what lives there.
Time to First Byte ~40%
The server builds the page. Slow hosting, no page cache and heavy database queries all live here.
Resource load delay <10%
The browser finds the hero image late — often because it is lazy-loaded, set as a CSS background or injected by a slider.
Resource load duration ~40%
The hero image downloads. Oversized JPEGs, no modern formats and no CDN make this long.
Element render delay <10%
The image has arrived but render-blocking CSS, web fonts or JavaScript still hold back the paint.
Source: web.dev — Optimize LCP
Why it pays
What a tenth of a second is worth to you.
In research commissioned by Google, Deloitte found that a 0.1 s mobile speed improvement was followed by 8.4% more retail conversions and 10.1% more in travel. Plug in your own numbers.
If your mobile site gets 0.1 s faster
$1,512extra / month
- Revenue today
- $18,000
- Extra orders / month
- 25
- Extra per year
- $18,144
Uses Deloitte’s average retail uplift (8.4%). A model, not a promise — real results depend on your audience and how slow the site is today.
Feel the difference
Same page. Different experience.
Drag the divider. On the left, the hero is still loading and an ad shoves the headline down mid-read. On the right, everything has its place before it arrives.
Most of the gain in WordPress speed optimization comes from unglamorous fixes: a page cache, a correctly sized hero image, reserved ad slots and fewer scripts in the way.
Before · LCP 4.8 s Hero image still loading, an ad pushes the text down, the menu ignores taps.
After · LCP 1.7 s Hero paints first, space is reserved for every element, taps respond instantly.
The evidence
Faster pages move real business numbers.
Three published case studies from Google’s web.dev — different industries, different metrics, the same direction.
Vodafone · LCP
31% faster LCP, 8% more sales
An A/B test on a landing page also lifted lead-to-visit by 15% and cart-to-visit by 11%.
redBus · INP
72% better INP, 7% more sales
Making the site respond faster to taps and clicks showed up directly in bookings.
The Economic Times · LCP + CLS
43% lower bounce rate
LCP went from 4.5 s to 2.5 s and CLS from 0.25 to 0.09 — both into the “good” range.
What we fix
Four layers, fixed in the order that pays off most.
01 / 04 — Server
Get the first byte back fast.
Full-page caching, object caching for the database, PHP and hosting tuned to your stack, and a CDN in front — usually the single biggest LCP win.
02 / 04 — Images & fonts
Ship a fraction of the bytes.
Modern formats, correct sizes for every screen, the hero image preloaded instead of lazy-loaded, and fonts that don’t reflow text.
03 / 04 — Plugins & scripts
Give the main thread back.
We profile every plugin, remove what you don’t use, and delay chat, ads and trackers until they’re needed — the core of a good INP.
04 / 04 — Layout
Stop the page from jumping.
Width and height on every image and embed, reserved space for ad slots and banners, and stable headers — so CLS stays near zero.
How it runs
WordPress speed optimization, from baseline to passing field data.
Every speed optimization change is made on a staging copy first. You see the numbers at each step, and nothing goes live without your OK.
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Record what real visitors feel
We pull your Chrome UX Report field data and run lab tests on each key template, so there is a fixed “before”.
- 28-day field data, mobile and desktop
- Lab traces for each template
- Plugin and script inventory
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Trace every slow metric to a cause
Each problem gets a named cause and a fix, ranked by impact, in a written plan you approve.
- LCP sub-part breakdown
- Long-task and script profiling
- Layout-shift sources mapped
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Make the changes where nothing can break
Server, images, scripts and layout — tested on staging against the same pages and devices.
- Caching and CDN set up
- Image and font pipeline
- Script diet and ad-slot reservations
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Ship it and prove it
We push live during your quietest hours and send a before-and-after report you can share.
- Lab before/after per template
- What changed and why
- Advice for keeping it fast
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Confirm it in Google’s data
Field data is a rolling 28-day window, so we check back once real visitors have caught up.
- Field data re-check
- Search Console CWV report review
- Fixes if anything regressed
After the project
Fast today. Still fast next year.
New plugins, embeds and campaigns slowly add weight back. Ongoing care catches regressions before Google’s 28-day window does.
- Monthly performance checksField and lab numbers reviewed every month, with a note when something slips.
- A second opinion on new pluginsAsk before you install — we’ll tell you what it will cost in speed.
- Updates that don’t undo the workCaching and optimisation settings re-checked after every major update.
Questions, answered
Do you guarantee a 100 Lighthouse score?
No — and be wary of anyone who does. Lighthouse is a single lab test; Google ranks on field data from real visitors. We target passing Core Web Vitals in the field, and confirm it with a follow-up check once Google’s 28-day data has caught up.
Is a caching plugin enough?
It helps Time to First Byte, which is roughly 40% of a good LCP budget. It does little for heavy scripts (INP) or layout shifts (CLS), which need changes to plugins, images and templates.
What is the difference between field and lab data?
Lab data comes from a single test run. Field data comes from real Chrome users over 28 days, and it is what Google uses for Core Web Vitals.
Why can field data take weeks to change?
Google reports a rolling 28-day average, so improvements show up gradually. That is why every WordPress speed optimization project includes a follow-up check 28 days after launch.
Will you change my theme?
Only if it is the main cause. Most speed optimization fixes work with your current theme. If you use one of our themes, we already know where to look.
Can ads and fast pages work together?
Yes, with care. We reserve space for ad slots and load ad scripts at the right time so they do not block content.
How do I keep the site fast afterwards?
New plugins and content can slow things down over time. Our care plans include monthly performance checks.
Get a free quote
Let’s build something great.
Tell us about your project and goals. A WordPress engineer — not a salesperson — will reply within one business day with a plan and a fixed price.
- Free, no-obligation quote within 24 hours
- NDA available on request
- Fixed price — you approve the scope before work starts
