Shopify Image Optimiser & Compressor

Shopify’s CDN doesn’t fix your images.
You have to.

Shopify converts images to WebP at delivery — but it converts whatever you upload. An 8 MB PNG uploaded to Shopify becomes an 8 MB PNG faithfully re-encoded as WebP. Garbage in, garbage out. AssetScope finds the oversized PNGs, bloated JPGs and images wider than 2048px in your store, shows you the exact saving before anything changes, and replaces them safely — scanning your Liquid theme first so no references break.

PNG → JPG conversion JPG re-compression Resize images >2048px Before/after preview Built-in safe replace
Try FREE — 30 Days on Us

FREE for 30 days  •  $1.99/mo after  •  Cancel any time

Three image problems Shopify silently ignores.

Shopify’s automatic WebP conversion is widely misunderstood. It doesn’t fix these three problems — and all three cost you page speed and lost sales.

PNG files used for photographs

PNG is lossless compression designed for graphics, not photos. A photographic PNG is typically 3–5× larger than the same image as a JPG at 80% quality. Every PNG product photo is adding unnecessary weight to your product pages.

Images wider than 2048px

Shopify product images are displayed at a maximum of 2048px wide. Uploading a 4000px image means every visitor downloads 4× more pixel data than needed. The extra dimensions are invisible but the bandwidth cost is very real.

No safe way to replace images in Shopify

Replacing a Shopify image changes its CDN URL. If any theme file hardcodes the old URL — a hero banner, a section setting — it breaks silently in production. Shopify shows no warning. AssetScope scans your theme before every replacement.

Scan, preview, optimise.

1

Run the Speed Audit

The speed audit identifies every PNG, oversized image, and bloated JPG in your store. Issues are grouped by product page with a priority score so you know where to start.

2

Preview the exact saving

Click any flagged image to open the Image Optimiser. You see a side-by-side before/after with exact before and after file sizes, dimensions, and format. Nothing changes until you confirm.

3

Save — theme scan runs first

When you save the optimised version, AssetScope scans every Liquid and JSON file in your active theme for the old image URL. Any hardcoded references are shown to you before the replacement completes.

Compress Shopify images. Convert PNG to JPG. Resize oversized files.

Preview the exact file size saving before anything changes. Batch-fix a full product page in under a minute.

Safe Replace included: Replacing a Shopify image changes its CDN URL. Theme files that hardcode the old URL break silently. Before any replacement, AssetScope scans every Liquid and JSON file in your active theme. If your hero banner references the image, you’ll see it listed before you confirm.

Everything in the Shopify image optimiser.

Convert Shopify PNG to JPG

Photographic PNG files converted to high-quality JPG at 85% quality. Typical saving: 50–80% file size. Pages load faster, more shoppers reach checkout, CDN bandwidth drops immediately.

Re-compress bloated JPGs

Bloated JPGs re-compressed at 80% quality. Typical saving: 30–50% with no visible quality difference. If the file is already lean, we leave it alone — no unnecessary re-compression.

Resize images wider than 2048px

Shopify displays images at a maximum of 2048px wide. Any image wider than that is delivering unnecessary pixel data to every visitor. AssetScope resizes to 2048px max while preserving aspect ratio.

Side-by-side before/after preview

Every optimisation shows you the exact before and after — file size, dimensions, format — before anything is saved. You know precisely what you gain before you commit.

Theme scan before replacement

Before saving the optimised version, AssetScope scans your active Liquid theme for hardcoded references to the old image URL. Any matches are surfaced to you before the replacement completes.

Batch process a full product page

Fix every image on a product page in one queue. What would take an hour of individual uploads takes minutes, with a preview before each save so there are no surprises.

Image optimisation is the highest-ROI fix in Shopify.

Images are the largest assets on any product page. Fixing them is the single fastest way to improve load time — and load time is directly tied to completed checkouts.

50–80%
typical file size reduction converting a photographic PNG to JPG at 85% quality
−7%
revenue recovered per second of page load time saved, per Deloitte & Google research
0
broken theme references — because AssetScope scans your Liquid files before every replacement

How Shopify’s image pipeline works — and where it falls short

When a visitor loads a Shopify product page, Shopify serves images through its global CDN and automatically converts them to WebP for supported browsers. This is widely misunderstood as “image optimisation.” It is not. WebP conversion changes the container format but applies no additional compression to the source file. A 6 MB PNG uploaded to Shopify becomes a 6 MB PNG re-encoded as WebP — still 6 MB.

Shopify does not resize images. If you upload a 5000×5000px product photo, Shopify displays it at the dimensions your theme requests — typically 800–2048px — but it serves the full 5000px source to every visitor. The browser scales it down visually, but every byte of that oversized image was downloaded first.

Shopify does not convert between PNG and JPG. PNG uses lossless compression optimised for graphics with flat colours: logos, icons, screenshots. For photographic product images, PNG produces files 3–5× larger than an equivalent JPG at 80% quality with no perceptible difference on screen. A store where someone uploaded PNGs for product photography — extremely common — carries an enormous and invisible bandwidth penalty on every product page load.

Shopify does not tell you when any of this is a problem. There is no built-in audit, no flag on the product listing, no speed warning in the admin. You only learn about oversized images when a speed test surfaces them — by which point they have already been hurting your conversion rate for months.

AssetScope’s Image Optimiser is a Shopify image resizer and compressor built directly into your admin. It identifies every PNG product photo, every image wider than 2048px, and every bloated JPG in your store, shows you the exact file size saving before anything changes, and replaces them safely — scanning your active Liquid theme for hardcoded references first so nothing breaks.

Shopify image resizer options compared

There are three ways to resize and compress Shopify product images. Here is how they compare.

Feature AssetScope Shopify native External desktop tool
PNG → JPG conversion
Resize images wider than 2048px
Re-compress bloated JPGs
Works inside Shopify admin
Before/after preview before saving Varies
Theme scan before replacement
No download / re-upload required
Includes 15 other Shopify tools

Common questions about Shopify image optimisation.

Does Shopify automatically compress and optimise images?
Shopify converts images to WebP format when serving them to browsers that support it, and serves them through a global CDN. However, Shopify does not recompress images, convert between PNG and JPG, or resize images that are wider than needed. It faithfully serves whatever you uploaded. An 8 MB PNG stays an 8 MB PNG — just delivered as WebP. The source file is what AssetScope optimises.
Should I use PNG or JPG for Shopify product images?
For photographic product images — the vast majority of Shopify product images — JPG is almost always the right choice. PNG uses lossless compression designed for graphics with flat colours and sharp edges (logos, icons, diagrams). Using PNG for a product photograph typically results in a file 3–5 times larger than the equivalent JPG at 80% quality, with no visible quality difference on a product page.
What is the ideal image size and dimensions for Shopify product images?
Shopify recommends 2048×2048px for product images displayed in square format, and a maximum width of 2048px for rectangular images. Images larger than this deliver more pixel data than Shopify can display, wasting bandwidth for every visitor. For file size, a well-compressed JPG for a product image should typically be under 200 KB. AssetScope flags anything outside these guidelines.
What happens if I replace an image in Shopify?
When you upload a new image to replace an existing one in Shopify, the new image receives a new CDN URL. Any Liquid theme file, section schema, or theme setting that hardcodes the old URL will immediately reference a broken link — silently, with no error shown in your admin. Hero banners and featured images are common victims. AssetScope’s safe replace scans your active theme before completing any replacement, surfacing any hardcoded references so you can update them first.
Can I undo an image optimisation in AssetScope?
AssetScope offers a “Download backup first” option before any conversion. If you download the original before saving the optimised version, you retain the original file. AssetScope saves the optimised image as a new file in your Shopify Files Library, so the original product image association needs to be updated manually if you want to revert. We strongly recommend downloading a backup for any image you’re not certain about.
Does the Shopify CDN mean I don’t need to optimise my images?
The Shopify CDN reduces latency by serving images from servers close to your customers, but it does not reduce file sizes beyond the WebP conversion. A 4 MB PNG served via CDN is still a 4 MB download for your customer — just from a nearby server. CDN delivery speed and image file size are independent variables. Optimising the source file is always worth doing regardless of CDN.
How long does it take to optimise Shopify product images with AssetScope?
Each image takes a few seconds to process — the majority of the time is the preview rendering, which runs before anything is saved. A typical store with 300 products and 900 images, processing only the flagged problem images, usually takes 20–40 minutes end-to-end. Because every image is previewed before it is saved, you are reviewing quality as you go rather than doing a bulk-apply and hoping for the best.
Is AssetScope’s image optimiser free?
AssetScope includes a 30-day free trial with no credit card required. After the trial, it is $1.99 / month, which includes all 16 tools — not just the Image Optimiser. The Image Optimiser, Speed Audit, and Bulk Image Lab are all included in a single subscription.
What is the difference between AssetScope and a standalone Shopify image resize app?
Most standalone image resize apps process images in bulk on their servers — you get a queue but no preview before images are replaced. AssetScope shows you a side-by-side before/after for every image before anything is saved. It also scans your Liquid theme for hardcoded references before replacement, which standalone apps do not do. And because AssetScope includes 15 other tools, you are not paying a separate subscription for image resizing alone.
Built with merchants, for merchants

We actually ship what you ask for.

AssetScope ships updates every few weeks, driven by real merchant feedback. If there’s a workflow we haven’t covered yet — or something in the app that could work better — tell us. We read every submission and most make it into the app within a few updates.

We read and reply to every request

30-DAY FREE TRIAL

Try AssetScope free for 30 days — no limits, on us.

Run your first Speed Audit, bulk edit your products, see exactly what it saves you — then decide. It’s $1.99/month after that. Less than a coffee.

Try FREE — 30 Days on Us
FREE for 30 days Hours of admin saved $1.99/mo — cancel any time