You lined up the perfect shot on your iPhone, the product looks crisp, and then the marketplace upload box throws back a grey error or simply refuses to accept the file. If this has happened to you, the culprit is almost certainly HEIC, the format your iPhone quietly saves photos in by default. It is a smarter, smaller format than the old JPG standard, but most e-commerce platforms still cannot read it. This guide explains what HEIC is, why it trips up product listings, and exactly how to convert your photos to JPG without losing quality.
What is HEIC, and why does your iPhone use it?
HEIC (High Efficiency Image Container) is Apple's implementation of the HEIF format, and it has been the default on iPhones since iOS 11 back in 2017. Instead of the decades-old JPEG compression, HEIC borrows techniques from modern video compression (HEVC, also known as H.265). That means variable-size blocks of up to 64 by 64 pixels rather than JPEG's fixed 8 by 8 grid, smarter prediction, and better entropy coding.
The practical payoff is dramatic. HEIC files are typically 40 to 50 per cent smaller than an equivalent JPG at the same visual quality. In real-world testing, JPEG files came out on average around 80 per cent larger than the same photo saved as HEIF, with the gap reaching as high as 96 per cent in some cases. HEIC also supports 16-bit colour depth compared with JPEG's 8-bit, so it holds a broader dynamic range and cleaner gradients.
In other words, HEIC is genuinely a better format for storing photos on your phone. The problem is not quality. The problem is where those files travel next.
Why HEIC breaks marketplace uploads
HEIC is reliably supported only inside Apple's own ecosystem and Safari 17 and above. On Windows, Android, and the overwhelming majority of web upload forms, it is a second-class citizen. HEIC is not part of the HTML specification's list of common image MIME types, so many upload forms reject it before it even reaches the server. That is why you see a flat refusal, a grey placeholder box, or a vague "unsupported file type" message.
None of the major marketplaces accept HEIC for product listings. Here is what they actually expect:
| Platform | Accepted formats | Key spec |
|---|---|---|
| Amazon | JPEG, TIFF, PNG, GIF | Main image: JPG, pure white background (RGB 255,255,255), 1000px minimum on the longest side, 2000-3000px recommended |
| Shopify | JPG, PNG (serves AVIF automatically) | 2048 by 2048px recommended for square shots |
| Shopee | JPG, JPEG, PNG | 500 by 500px minimum, 2 MB hard cap per image |
| Lazada | JPG, JPEG, PNG | 330 by 330px minimum, up to 2000 by 2000px, 3 MB cap |
| Qoo10 / Carousell | JPG, JPEG, PNG | Standard web formats only, no HEIC |
Notice the pattern: JPG (JPEG) is the one format every single platform accepts. It is the safest, most universal choice for product photography. HEIC appears on none of these lists.
What about Instagram and Facebook?
Social platforms are a little more forgiving. Instagram and Facebook will accept a HEIC upload, but they convert it to JPG or WebP internally the moment it lands. That means you gain nothing by handing them a HEIC file, and you hand over control of the quality settings to their compression engine. You are far better off converting the file yourself first, so you decide how much quality to keep.
The two ways to stop fighting HEIC
There are really only two approaches: stop your iPhone creating HEIC files in the first place, or convert the HEIC files you already have. Most sellers need a bit of both.
Option 1: Change your iPhone camera format
If you have not shot your product photos yet, this is the cleanest fix. On your iPhone, go to Settings, Camera, Formats and choose Most Compatible instead of High Efficiency. From that point on, the camera captures straight to JPG. The trade-off is larger files on your phone, but for a product-photography workflow that is a price well worth paying, because every photo you shoot is upload-ready.
Keep in mind this only affects new photos. Anything already sitting in your camera roll as HEIC stays HEIC, so you will still need Option 2 for your back catalogue.
Option 2: Convert your existing HEIC files to JPG
For photos you have already taken, you need to convert. A few points to get right:
- AirDrop can trick you. When you AirDrop a HEIC photo from an iPhone to a Mac, it usually arrives as HEIC. But depending on your settings, some transfers auto-convert to JPG. Never assume, always check the file extension before uploading.
- Emailing to yourself often converts. Mailing a photo from the iPhone Photos app frequently converts it to JPG, but it can also strip resolution, which is the last thing you want for a zoomable product shot.
- Batch conversion is essential at volume. Converting photos one at a time is fine for a single listing, but if you are preparing dozens of SKUs you need a tool that handles a whole folder at once and lets you set the output dimensions and quality.
Because product images almost always need to be resized and squared for each marketplace anyway, the smart move is to convert and resize in a single pass. A browser-based tool such as PixelPrep lets you drop in your iPhone photos and export clean, correctly sized JPGs ready for Shopee, Lazada, Amazon, Shopify, Qoo10, or Carousell, without installing desktop software or wrestling with camera settings.
Does converting HEIC to JPG hurt quality?
This is the question every seller worries about, and the honest answer is: only slightly, and only if you do it carelessly. HEIC is the more efficient format, so a JPG will always be a larger file for the same visual result. But converting a well-exposed HEIC to a high-quality JPG (say 85 to 90 per cent quality) produces an image that is visually indistinguishable to a customer scrolling a product page.
The mistakes that actually damage quality are these:
- Converting at low quality settings. Dropping to 60 per cent quality to save file size introduces visible blocking and colour banding. Stay at 85 per cent or higher for product photos.
- Converting the same file repeatedly. Each JPG save is lossy. Convert once from the original HEIC, then keep that master JPG rather than re-exporting it again and again.
- Downsizing before you mean to. Email and messaging apps shrink resolution silently. Always convert from the full-resolution original.
Do it properly and the quality difference is academic. Do it sloppily and you will see it in the customer's zoom view.
A simple, repeatable workflow
Here is a workflow that keeps HEIC from ever slowing you down again:
- Set your iPhone camera to Most Compatible so new product shots save as JPG automatically.
- For older HEIC photos, convert from the full-resolution originals, never from an emailed or messaged copy.
- Convert and resize in one step, exporting square JPGs at 85 to 90 per cent quality sized to each marketplace's spec.
- Keep a clean master JPG per product so you never re-compress the same file twice.
- Always confirm the file extension reads .jpg before you hit upload.
The takeaway
HEIC is not a bad format. It is a genuinely superior way to store photos, and Apple was right to adopt it. But e-commerce runs on JPG, and every marketplace that matters, from Amazon to Shopee, expects it. The fix is straightforward: switch your camera to Most Compatible for new photos, batch-convert your existing library to JPG, and always resize to the platform's dimensions in the same pass. Get that habit in place and the grey error box becomes a thing of the past, leaving you free to focus on the photography itself.