Miko Bulk Image Resizer Guide

1. Overview

Miko Bulk Image Resizer works on the images that are already on your store. It handles product images and collection images, and it changes them in place. You never download a file and you never upload one back. You choose how your images should look, check a preview built from your own photos, then run it. Every original is kept for 30 days, so any run can be undone. No theme changes, and no customer or order data is read.

Key capabilities

• Resize in place, on product images and collection images, with no downloading or re-uploading
• Five resize modes, from a simple longest-side cap to an exact frame, a percentage, a target file size, or a watermark on its own
• Preview before you commit, built from your own photos, with real dimensions and file sizes
• Undo, restore a whole run or a single image with one click for 30 days
• Image Health, a free read of your catalogue that finds oversized images, missing alt text and inconsistent shapes
• Bulk alt text, template based, with its own undo, and never charged
• Watermarks, your logo in one of nine positions, with a live preview
• Filenames, keep your own or rebuild them from the product title
• Scheduled runs, weekly or monthly, plus an option to tidy new products as they are added

2. Getting Started

Miko Bulk Image Resizer installs from the Shopify App Store. There is nothing to pay to install, and your first 100 images are included.

Step-by-step

1. Go to apps.shopify.com/miko-bulk-image-resizer and click Install.
2. You will be sent to your Shopify admin to approve the app's permissions. Miko asks to read and write products only. That covers product images and collections. It never asks for customers or orders.
3. The app opens inside your Shopify admin under Apps → Miko Bulk Image Resizer. The left-hand menu holds Resize Products, Resize Collections, Image Health, Watermark, Alt Text, History, Settings, Billing and Help.
4. Open Image Health first. It costs nothing, it changes nothing, and it tells you what your catalogue actually needs.

3. Choosing a Resize Mode

The mode decides what happens to the picture. Everything else is a detail on top of it. Pick the one that matches the job.

The three fit styles

When you choose Width and height, you also choose how each photo is placed into that frame.

• Fit inside, the whole image sits inside the frame and keeps its own shape. Nothing is cut off. Images that already fit are left alone.
• Crop to fill the frame, the image fills the frame exactly, centred, and the edges that do not fit are trimmed. This one can enlarge a smaller image, which is how you get a grid where every card is the same size.
• Pad to an exact size, the whole image is kept and the gaps are filled with a background colour you choose. Nothing is cut off and every image ends up the same size.

The controls that sit on top

• Quality, a slider that trades file size against detail.
• Output format, keep the original format, or convert everything to JPEG, WebP or AVIF.
• Strip camera and EXIF metadata, removes the camera model, the software name and any GPS location left in the file by the photographer.
• Skip anything already the right size, leaves images that already meet your settings untouched.

4. Preview Before You Commit

Bulk changes should never be approved from a description. Before anything is written, press Preview and Miko takes a few real photos from the selection you made, runs them through the exact same process the full run will use, and shows you the before and the after side by side.

What the preview tells you

• The picture, so you can see the crop, the padding, the colour and the watermark before you agree to it.
• The numbers, the dimensions and file size before and after. These are measured on the full size result, not on the small picture on your screen.
• How many images the run will cover, and what it will cost.
• Samples that would not change, shown with the reason, so you are not left wondering why one looks identical.

5. Choosing Which Products

You decide how much of the catalogue a run covers. On the Resize Products screen you have four choices.

• The entire catalogue, every product image in the store.
• Specific products, picked by hand from Shopify's own product picker.
• By collection, choose a collection and Miko works out which products are in it.
• By tag, vendor or product type, useful for one brand, one season, or one supplier's photos.

The Resize Collections screen works the same way for collection images, with the whole catalogue or hand-picked collections.

6. History & Undoing a Run

Every run is listed under History, newest first, with what it covered, how many images were changed, how many were skipped, and when it finished.

Restoring

1. Open History and find the run.
2. Press Restore to put every image in that run back the way it was.
3. Or open the run to see each image, with its real before and after, and restore a single image on its own.

A restore runs in the background in the same way a resize does. Miko puts the original back and removes the resized copy.

7. Image Health

Image Health is a read of your whole catalogue. It costs nothing and it changes nothing. Run it before your first resize, and again whenever you want to see where you stand.

It reports four things.

• Images over your size target, the ones weighing your pages down.
• Images with no alt text, which matters for search and for shoppers using a screen reader.
• Your largest images, listed so you can see the worst offenders by name.
• Aspect ratio consistency, whether your photos are all the same shape, or whether your grid is a mix of squares, portraits and landscapes.

If the report suggests a shape, choosing it only pre-fills the resize screen for you. You still see the preview and you still press the button yourself.

8. Bulk Alt Text

Alt text is the short description behind an image. Search engines read it, and so do screen readers. Writing it by hand across a catalogue is the reason most stores never do it, so Miko fills it from a template.

Building the template

Write a sentence and drop in tokens where the details should go. Miko replaces them per image.

• {product}, the product or collection title
• {vendor}, the vendor or brand
• {type}, the product type
• {position}, the image number, so the second photo reads differently from the first
• {shop}, your store name

A live table shows the before and after for real products as you type, so you can see the sentence your shoppers will get. Any token with nothing behind it is dropped cleanly rather than leaving a gap.

9. Watermarks

Upload your logo once on the Watermark screen and Miko remembers it. A PNG with a transparent background gives the cleanest result.

• Position, one of nine spots on a three by three grid, from a corner to the centre.
• Size, set as a share of the image width, so the stamp stays in proportion on a large photo and a small one.
• Opacity, from a faint mark to a solid one.
• Margin, how far the stamp sits from the edge.

The preview stamps your logo onto one of your own product photos and updates as you move the sliders, so you are judging it on a real image rather than a sample.

Once it is set, a watermark can go on as part of any resize run, or on its own using the Watermark only mode, which leaves the pixel size untouched.

10. Image Filenames

A resized image is uploaded again, and the filename it is uploaded under becomes its permanent address on Shopify's CDN. Google reads that filename, so this is a search decision rather than a cosmetic one. You choose, in Settings.

• Keep my filenames, the default. Your existing names carry over exactly as they are. Renaming your files is not a decision Miko makes for you.
• Rename for SEO from the product title, names are rebuilt from the product title and numbered in the order the images appear, so IMG_4821.jpg becomes something like blue-ceramic-mug-2.jpg.

Whichever you choose, it applies to every image the app writes from that point on. Images you have already resized keep the names they were given at the time.

11. Scheduled Runs

Once your settings are the ones you want, you can stop thinking about images altogether.

• A weekly or monthly schedule, Miko runs your saved default settings across the catalogue on its own. Images that already match are skipped, so a schedule on a settled catalogue does very little and costs very little.
• Resize new products automatically, an optional setting that tidies a product's photos shortly after it is added, so new listings arrive already matching the rest of the store.

12. Billing & Limits

There is no monthly fee. You pay for the images you actually change, and you set the ceiling.

Your monthly spending limit

On the Billing screen you set the most you are willing to spend in a month. Miko counts what it has charged against that number. When the limit is reached, the run pauses, the remaining images stay queued, and you are told. Raise the limit and the run picks up where it stopped. Leave it, and nothing else is charged that month.

See how Miko Bulk Image Resizer sits alongside the rest of the family. View full pricing →

13. Troubleshooting & FAQ