Website maintenance
Core Web Vitals optimization to make a slow website fast again
PageSpeed report in the red? We find what slows your site, fix the causes by impact and retest the same pages.
What Core Web Vitals measure
Core Web Vitals are three numbers Google uses to describe how a page feels to a real visitor: how fast the main content appears, how quickly the page reacts when someone taps, and whether things jump around while it loads. Optimization means moving all three into Google's "good" range on the pages that matter to your business.
| Metric | In plain words | Good, per Google |
|---|---|---|
| LCP, Largest Contentful Paint | When the biggest image or heading has appeared | 2.5 s or faster |
| INP, Interaction to Next Paint | How long the page takes to respond to a tap or click | 200 ms or less |
| CLS, Cumulative Layout Shift | How much the layout moves while loading | 0.1 or less |
Google judges these at the 75th percentile, split by mobile and desktop, so a page passes only when three out of four visits meet the mark.
Lab data and field data are different
PageSpeed Insights runs a single simulated test on a throttled phone. Search Console reports what real Chrome users experienced over recent weeks. That is why a site can score 45 in the lab and still pass in the field, or the reverse. Our guide on reading Google Search Console Core Web Vitals and PageSpeed reports explains each panel. We work from both, and we trust field data more.
What speed does for rankings
Google says Core Web Vitals are used by its ranking systems, but also that good scores alone do not lift a page that is less relevant than its competitors. Speed helps most with what happens after the click: fewer visitors giving up before the page loads, and more of them reaching your form.
Why do sites in Thailand load slowly?
The causes we test for first are rarely exotic. On sites built for the Thai market, these are the usual suspects:
- Page builders. Visual builders load their own scripts and styles on every page, used or not.
- Oversized photos. A 5 MB phone photo uploaded straight into a slider is common, especially on hotel, food and property sites.
- Thai web fonts. Thai script needs larger font files than Latin. Loading several weights of two Thai fonts from a third-party server can delay the first readable text.
- Third-party scripts. Chat widgets, tracking pixels, embedded maps and review badges each add requests and slow down taps.
- Hosting. A cheap shared server far from Thai visitors, or one without caching, puts a floor under every page.
If you want to diagnose a WordPress site yourself first, our guide on why a WordPress website is slow walks through the checks in order.
How we speed up a site
Speed work is a defined project, not open-ended tinkering. Each step produces something you can see. A content delivery network is one tool among several; our guide to Cloudflare for websites explains when it helps and when it does not.
- MeasureRecord lab and field numbers for your key templates: home, a service or product page, the booking or checkout page.
- PrioritiseList the causes by how much time each one costs, and fix the biggest first.
- FixResize and convert images to WebP, trim fonts to the weights you use, remove or delay unused scripts, add caching.
- Put a CDN in front where it helpsOnly when the measurement shows distance or server load is part of the problem.
- Retest and reportThe same pages, the same tools, before and after, in a short written report.
Should you optimise or rebuild?
Some sites cannot be made fast without starting again. If the theme is a heavy multipurpose template with a page builder woven through every page, removing the builder is effectively a rebuild. We tell you this after the measurement step, before you pay for fixes that will only move the score a few points.
Two questions decide it: is the design still right for the business, and is the structure underneath clean? If the design works but the code is heavy, it is a development problem; if both need to change, you need a redesign too. Our article on website design vs website development explains the difference. Once a site is fast, keeping it fast is part of our website maintenance services.
Booking and checkout pages
The pages worth the most attention are the ones where money changes hands. For example, a Pattaya resort might have a fast home page but a room page loaded with a 30-photo gallery and a booking widget script, so the "Book now" button reacts slowly on a guest's phone. That page gets fixed first. The same thinking shapes how we design new properties from the start, which you can read about on our hotel web design page. On stores, the product page and the PromptPay checkout step get the same priority.
Pricing
Speed projects are priced per site after we run the first measurement, because the work depends on what we find. Ongoing care after the fix is quoted separately; see how maintenance pricing is worked out. When a rebuild is the better answer, the one-time build packages from Website Development Bangkok, a web development company in Thailand, are the starting point, and our pricing page compares them.
Speed guides
Read these if you want to understand your reports first. When you are ready, send us your site address and ask for a price for your project.
SEO, speed and analyticsCloudflare and your hosting: what it adds, and what it cannot replace
Cloudflare is a proxy, CDN and DNS layer in front of your host, not a replacement for it.
SEO, speed and analyticsHow to read a speed test and the Google Search Console Core Web Vitals report
How to read PageSpeed Insights, GTmetrix and the Search Console Core Web Vitals report: lab vs field data, LCP, INP and CLS thresholds, and validating fixes.
SEO, speed and analyticsWhy your WordPress website is slow, and how to fix each cause
Twelve causes of a slow WordPress site, from hosting and PHP to page builders, Thai fonts and WP-Cron, and which fixes need a plugin versus a rebuild.
ComparisonWebsite design vs website development, explained for business owners
Web design plans how a site looks and works for people; web development builds it in code. What each covers, what it costs and who to hire.
SEO, speed and analyticsImage optimization for websites: a practical guide for business owners
Practical rules for website images: format, size, compression, srcset, lazy loading, layout shift and bilingual alt text, plus an upload routine for staff.
Common questions
Will you promise a perfect 100 PageSpeed score?
No, and we would be wary of anyone who does. A lab score changes between runs, and some scripts you may need, such as a booking engine or a chat widget, cost points you cannot remove. We aim to move the pages that earn you money into Google's good range for real visitors, and we show before and after numbers so you can judge the result.
Why is my site slow on mobile but fine on desktop?
PageSpeed tests mobile on a simulated mid-range phone with a slow connection, while desktop gets a fast processor and network. Heavy images, large Thai font files and JavaScript that must run before the page responds hurt far more on a phone. If most of your customers find you on their phones, the mobile result is the one to fix first.
Does site speed affect Google rankings?
Google states that Core Web Vitals are used by its ranking systems, but relevance comes first, so a fast page with weak content will not outrank a better answer. Treat speed as one signal among many. Its clearer benefit is on your own numbers: fewer people leaving before the page appears and more of them finishing a booking or enquiry.
Will Cloudflare make my site faster?
Often a little, sometimes a lot, occasionally not at all. A CDN serves images and files from locations closer to visitors and can cache whole pages. It does not fix a slow theme, oversized photos or a database that takes seconds to answer. We decide whether to add it after measuring, and configure it so forms and checkout still work.
Is it better to rebuild than to optimise?
It depends on what the measurement shows. If the slowness comes from images, caching and a few plugins, optimising is cheaper and quicker. If a page builder or a bloated theme sits under every page, fixes hit a ceiling and a lean rebuild usually costs less in the end. We give you both options with prices when the choice is close.
Related pages
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