Job landing-page-speed-fix-within-builder-limits · revised 11 October 2026
Make one slow landing page on your site builder meet an agreed weight and speed budget
One page on Webflow, Squarespace or Wix is brought under a page-weight and lab-speed budget agreed from a measured baseline, without a redesign, using only what the builder allows.
You might be seeing
- The page takes several seconds to show its main image or headline on a phone
- A speed test names large images, third-party scripts or many fonts
- The page was fast until a video, widget, extra font or tracking tag was added
No passwords, keys, card details or admin invites needed to start.
What usually happened
On a hosted builder the server and caching are not yours to change, so speed depends on what you put on the page: image sizes, fonts, videos, third-party scripts and embedded apps. Teams often chase a score instead of finding which few items make up most of the weight.
Who it’s for: Marketer or owner who sends paid or email traffic to one landing page on a site builder and sees it load slowly, especially on a phone.
Usually starts when: A speed test flags the page, a campaign page feels slow on mobile, or the page got heavier after new images, videos or tracking tags were added.
The result: The named page meets a total-weight limit and a median Largest Contentful Paint (the lab time for the largest content item to show) agreed in writing from a baseline measured five times, with no change to its design other than the items named.
Check whether this job fits
Answer these without sending logins. Nothing is submitted unless you choose to contact us.
Checks you can run yourself
Sort the files by size
Open the page in a desktop browser, open the developer tools network panel, reload with the cache disabled and sort the requests by size.
Look for: Usually a handful of images, one video or one script account for most of the bytes. Those are the targets.
What you get
- The baseline and after measurements, side by side
- The ranked list of what made up the page weight and what was changed
- A list of what the builder does not let you change, and any item left for your decision
Included
- One page on one Webflow, Squarespace or Wix site
- A baseline of five runs of the same Lighthouse test, with its default mobile settings (simulated 150 ms latency, 1.6 Mbps download and a 4x CPU slowdown), and a list of every file and script on the page by size
- Changes the builder allows: resizing and recompressing images, loading below-the-fold images lazily, trimming fonts, replacing animated images with video, deferring or removing scripts, moving heavy embeds off the page
- A repeat of the same five-run test after the work
- A budget agreed in writing only if it asks for at least a 20% smaller total weight and a median Largest Contentful Paint at least 20% shorter than the baseline
Not included
- A redesign, new copy or new images
- A guarantee about search ranking, advertising quality scores or real-user performance data
- Moving the site to another host or adding a content delivery service outside the builder
- Removing marketing tags without your decision on which to keep
How we know it’s done
Agreed with you before work starts. Each check produces evidence you keep.
Total transferred weight of the named page, measured with the cache disabled on a desktop browser, is at or below the figure agreed in writing from the baseline.
Evidence: Before and after network panel totals.
The median of five repeat Lighthouse runs, with the same Lighthouse version, machine and default mobile settings as the baseline, shows Largest Contentful Paint at or under the agreed time, and no worse total blocking time than the baseline.
Evidence: All ten runs listed with the tool, settings and date.
No image on the page exceeds the per-image limit agreed in writing.
Evidence: A list of every image with its size.
Desktop and phone views show no change other than the named items, and the form or widget on the page still works.
Evidence: Side-by-side screenshots and a test of the form or widget.
Sign-off. You compare the page before and after on your own phone and desktop and sign off before payment. Your account holder publishes.
If it fails. If the agreed checks fail, you do not pay for this fixed scope. We hand over the findings and agree whether to stop or re-quote; no surprise work.
When it fits, and when we stop
It fits when
- The page is public and a speed test can reach it
- You can tell us which images, scripts and embeds are essential
- You can edit or give access to the page in the builder
We stop and tell you if
- Most of the weight is a third-party app or frame that the builder cannot optimise and you will not remove
- The page is slow only because of your local connection or a short outage at the builder
- The target set would need a redesign, which is outside this job
- The baseline and ranked list show that a budget at least 20% under the baseline in both total weight and Largest Contentful Paint cannot be met within what the builder allows; we stop there and you pay nothing
What could go wrong
Original images and any removed script text are kept in the handover. Each change is one setting or file you can put back.
Scroll the table sideways to read it all.
| Risk | How we handle it |
|---|---|
| Lab scores vary from run to run and from tool to tool. | We use the same tool and settings, take the median of five runs and report the spread, not a single score. |
| Compression makes images look worse. | You see before and after versions at both widths and approve any quality loss. |
| Removing a script breaks tracking or a form. | Nothing is removed without your decision, and the form and tag checks are re-run after the change. |
An independent reviewer checks the redacted before and after evidence, the list of changes and the way back, and looks separately at anything that touches customer data, payments or logins, before you see the result.
How we deliver
We arrange the work and independent review, then show you the result against the agreed checks. You keep authority over your systems.
- Agree the page, the essential items and how the speed is measured
- Measure the baseline five times and list every file and script by size
- Rank the items and agree the budget in writing from the baseline
- Make the allowed changes to the page, using a duplicate page or an unpublished draft where the builder offers one; your account holder publishes only after review
- Repeat the five-run test, compare visually at desktop and phone width, and have a separate reviewer check the numbers
- Hand over the measurements, change list and steps to undo; your account holder publishes
This is a one-off job, not emergency cover or a subscription. We confirm eligibility, the total price, a start window and a delivery date before you accept. Work starts only after agreed inputs, secure access and necessary permissions are in place. Builder plan, app, domain and payment-provider charges are yours and are excluded unless the written quote includes them. No charge or booking is created by an enquiry.
Need to keep it working?
If pages get heavier as you add content, a monthly speed and weight check is available as a separate standing service.
Ongoing work is separately scoped and quoted: no monitoring, response-time guarantee or automatic subscription is included in this job.
Explore an ongoing engineering lane, or mention the responsibility you need in your enquiry.
What you can check
This is a new service. We have not delivered this job for a client yet.
Other ways to get this done
- Squarespace's own page-size guide suggests keeping pages to about 5 MB and images under 500 KB, which many owners can apply themselves. support.squarespace.com
- Wix's site performance articles list what Wix handles and what remains yours. support.wix.com
Questions
Will this raise my search ranking?
We make no promise about ranking. We measure page weight and lab loading time and report both.
Can you pass Core Web Vitals?
Those are field measurements from real visitors over time. We report lab results and name what is likely to help; we cannot promise the field figures.
Will the page look different?
Only where an agreed change needs it, such as a smaller image or a removed animation. You see before and after versions first.
What if my page cannot be made much faster?
The budget must ask for at least a 20% smaller total weight and a 20% shorter median Largest Contentful Paint than the baseline. If the baseline shows the builder will not allow that, we stop after the baseline and ranked list and you pay nothing.
Send an enquiry
Send us
- The page address and the builder
- The result of any speed test you have run, with its date
- Which items on the page are essential, such as a form, a booking widget or a specific video
Later, once you agree
- Builder access at the role named in the access section, set up by you and removable at any time
- The original images in their largest versions, if you have them
- Your decision on every tracking tag or app the baseline lists
You keep the live site, the builder account, the domain and all customer data. Access is agreed with you in writing before any work starts, and no work starts until it is. Any access we use is through a company-controlled account, never a personal login. The role depends on the builder. Webflow: the Designer or Site manager role, on a paid full seat in your Workspace (or a guest invitation, which Webflow allows only to a Freelancer or Agency Workspace); changing scripts needs the custom code section, which Webflow gives only to those two roles. Squarespace: the Administrator permission, because only owners and administrators can make design changes (such as fonts) or add code injection. Wix: the Website Manager role; Wix's pages do not say which role reaches every setting this job touches, so we confirm that in your dashboard before quoting. We name the exact role and any seat or plan charge in the quote before you invite anyone; those charges are yours. You can remove our access at any time. No passwords or payment details go by ordinary email, and your authorised account holder publishes the final change.
Email fallback: open your mail app
If website submission is unavailable, review and send the fallback email yourself. An email fallback is not a website receipt. Or write to hello@syntheticindustry.ai with “landing-page-speed-fix-within-builder-limits” as the subject.