Run & Advise

Shopify Speed Optimisation

Fix what is actually slow.

Shopify speed optimisation from a team with 100+ Shopify builds behind it. We measure what your customers actually wait for, name what is costing the time, usually the app stack rather than the theme, then fix it and set a budget that holds.

The stores we build and look after.

100+ builds Shipped since 2018

Certified, not badge-only

Founder-led Not account-managed

Two brands we run Our own money on the line

Most slow stores were not built slow. They got slower, one app at a time.

100+ builds shipped
Founder-led, not account-managed
Trading on our own two brands

Read the case studies

A shopify speed optimisation uk search usually comes from somebody who has already been quoted a plugin that promises a score and would rather have a person find what is actually slow. Shopify site speed on most stores comes down to a short list: apps loading script on every page, images sent at the wrong size, and theme code doing at load time what could wait until after it. We start by measuring, so the fix is aimed at the page your customers see slowly rather than the one a test tool happens to like.

Audit and strategy

Four stages, one team

How we make a Shopify store faster

Measured before anything changes and measured again after, so every gain is one we can prove.

Measure

Field data and lab data together, across templates rather than just the homepage. Product and collection pages are usually slower than the page everyone tests, and they are where the money is.
Diagnose and Prioritise

Every cause identified and ranked by how much time it costs against how hard it is to remove. You get that list whether or not you ask us to do the work.
Fix

Changes made on a preview theme and measured one at a time, so we can prove which change did what rather than shipping ten at once and claiming credit for the total.
Set the Budget and Re-Measure

The agreed limits written down, and a follow-up measurement after the store has been live with them. Speed work that is not re-checked is speed work that lasted a quarter.

Fix

The causes named, ranked and removed one at a time, on a preview theme, so every change can be proved rather than claimed.

Powerlete

Our own brand, rebuilt for speed

Shopify site speed

We rebuilt our own store for speed first

Powerlete is our own sportswear brand. It ran on a heavier, feature-rich theme with room to improve, so we rebuilt it properly: for speed, for conversion and for functionality.

It is also where we test changes first, on our own money, before they go anywhere near a client build. When a script earns its place there, we know what it costs, because the cost is ours.

Read the case study Shopify theme development

What you get

What our Shopify speed optimisation service covers

Three parts, in this order, because a fix aimed without a diagnosis is a guess.

Diagnosis

Field data first

What your visitors experience on their own phones and connections, not one lab run on a desktop.

The app and script audit

What is loading, what is dead, and what has to stay but can wait until the page is usable.

The fixes

Core Web Vitals, one at a time

LCP is usually an image or a font, INP usually JavaScript, CLS usually something arriving late.

Images and fonts

Right sizes and formats, real lazy loading below the fold, and fonts that never hold the page blank.

Theme-level work

Render-blocking resources, oversized bundles and sections doing expensive work nobody scrolls to.

Keeping it

A written budget

Limits for scripts, images and third-party load, agreed with you and documented.

Measured again

Checked once the store has lived with the changes, because a number nobody checks stops being true.

Hold

A written budget for scripts, images and third-party load, and a second measurement once the store has lived with it.

Fittr Nutrition

Our own brand, built and run

Shopify speed optimisation UK

A standard build, kept quick on purpose

Fittr Nutrition is our supplements brand. We built it as a clean, fast-loading Shopify store, and we run it the way we would run a client’s: the same stack and the same arguments about what is worth paying for.

It is a standard Shopify build rather than a bespoke performance build, which is what makes it useful. Most stores do not need exotic work to be quick. They need somebody to decide what loads, and to keep deciding.

Read the case study Maintenance and support

A speed app vs a diagnosed fix

Why our Shopify speed optimisation holds

The quick version is a plugin that promises a score. The difference between that and a diagnosis is where each one looks, and what is left once it has finished.

Question	A speed app	A diagnosed fix
What it measures	A lab score on one page	What your visitors wait for, on their phones
Which pages	Usually the homepage	Product and collection templates too
The app stack	One more app loading on every page	Dead apps removed, the rest deferred
How changes ship	All at once	One at a time, each one measured
What you keep	A number	A ranked list of causes, yours either way
Three months later	Nothing checks it	Re-measured against a written budget

Read: Best ecommerce platform for SEO

Reviews on the Shopify Partner Directory

Merchants, in their own words.

From start to finish, they were incredibly easy to work with. They understood the brief perfectly and delivered to a very high standard. Communication was excellent throughout, with quick and clear responses to any questions I had.

Tacky And Upsetting Store build or redesign · April 2026
The things [the team] have put in place and recommended for us have paid immediate dividend. We wish we had come in contact with [them] sooner.

ARTMARTIAL Store build or redesign · April 2026
I can’t recommend [the team] enough, [they] helped us with everything from product design, supplier communication to website building and SEO. We were able to build a brand off the back of all [their] information and help.

Reveliér Studios Business strategy guidance · April 2026

Read the reviews on the Shopify Partner Directory

How we work with you

Speed audit

Field and lab data across your templates, and every cause ranked by the time it costs against the effort to remove it. The list is yours whether or not you ask us to do the work.

Short engagement

Speed fix

The fixes made on a preview theme and measured one at a time, then a written budget and a second measurement once the store has been live with the changes.

Fixed scope

Held on a support plan

Core Web Vitals measured monthly against the budget agreed for your store, as part of maintenance and support, so the next app install does not quietly undo the work.

Retainer

Is this the right thing to buy from us?

Worth a conversation

Product and collection pages feel slow on a phone
Core Web Vitals are failing in Search Console and nobody can say why
Apps have been installed over the years and none ever removed
A speed app moved the score and nothing customers noticed

Probably not this, yet

The store is quick and simply not converting
The theme is years old and the real brief is a redesign
You want a score of 100 as the goal in itself

Conversion rate optimisation, if it is the store

Shopify speed optimisation services

Where this fits

Shopify speed optimisation services get sold under several names. Shopify performance optimisation, page speed optimisation and, spelled the American way, Shopify speed optimization are one piece of work under different labels. What varies between suppliers is whether anyone measures before they change anything, and whether anyone measures again afterwards.

Speed also sits next to three other jobs, and it is worth knowing which one you need. A store that is fast and still not selling needs conversion work. A theme that is itself the problem may need rebuilding rather than tuning. And a store that was quick a year ago needs a budget somebody checks every month, which is what our maintenance plans carry.

Keep reading

Everything around a faster store

Around speed

Read first

See the work

The brands behind the stores we build and run.

Partners

Tools we have already run on our own stores

The apps around a Shopify store decide as much as the theme does, and choosing between thousands of them is most of the work. We are a Shopify Plus Partner and we integrate the tools that sit around the platform. Every one of them runs on our own two stores before it reaches a client, so the recommendation you get comes from having paid for the thing and lived with it. When a brand already runs a stack that works, we integrate with it rather than rebuilding it to suit us.

How we use them

Our own app Parity, on the Shopify App Store

Straight answers

Will a speed app fix it?

Rarely on its own. A speed app is one more thing loading on every page, and it cannot remove the apps and script that are costing the time. Where the theme or the app stack is the problem, we fix that directly, which is cheaper to keep and easier to prove.

Should we be chasing a PageSpeed score of 100?

No. The score is one lab run on one page. Google ranks on field data, what real visitors on real phones experience, and that is what we measure and report. A lab run is useful for finding causes, not as the goal.

Do we have to remove apps we actually use?

No. Apps that earn their place stay. The ones that load on every page can often wait until the page is usable, and the ones nobody has used in a year come out. You decide on each one from the list.

Will the store look different afterwards?

Not unless you want it to. Most of the work is invisible: what loads, when, and at what size. Where a design choice is the cost, a hero video for instance, we show you what it costs and you decide.

Does site speed affect Shopify SEO?

Core Web Vitals are part of how Google assesses a page, and a slow page loses visitors before they read anything. Speed rarely wins rankings on its own. It stops a slow page giving away what the content earned.

Can you work on a theme another agency built?

Yes. The diagnosis reads what is loading before anything changes, so it does not matter who wrote the theme or installed the apps.

Will you show us before and after numbers?

For your store, yes. Every change is measured on a preview theme before it ships, and the store is measured again once it has been live with them. We do not publish standing figures for our own stores, because a live store’s number stops being true the next time anyone ships.

What stops it slowing down again?

A budget. We agree limits for scripts, images and third-party load, write them down and re-measure against them. On a maintenance plan that check happens every month.

Send us the page that feels slow

Send the store URL and the template customers complain about. We reply personally, and if the honest answer is that speed is not the problem, that is the reply you get.

Stores we build and grow