About this site
- 18 platforms
- 51 specs
- 13 source domains
- Images never leave your device
This is a one-person site. I look up the numbers, write the code, and maintain the thing. There is no company, no team, and no editorial department behind it. I built it because I kept opening four tabs to answer one question: how big does this listing image actually have to be?
One batch of photos usually has to work on four or five marketplaces at once. Each one wants a different pixel size, a different aspect ratio, its own rule about background, and its own file-size cap. Those rules live in help centers, seller-center notices, agency blog posts, and forum threads, and none of them are dated clearly enough to trust on sight.
So this site does two things. First, it collects the requirements that can be found into one table you can read by platform. Second, it pairs that table with a tool that produces images at exactly those specs: pick a platform and a rule, drop your files in, and the tool handles size, padding, and the file-size cap together.
The tool runs inside your own browser. Your images are never uploaded, so there is no "upload and download again" step, and no server that could keep a copy.
Where the numbers come from
To be straight with you: not every number here comes from an official platform document. They fall into three groups.
- 1. The platform publishes it
- Requirements stated publicly in a help center, a seller policy page, or a developer documentation site. These are used as published, and the source domain is the platform own domain.
- 2. It is only visible in the seller center
- Some platforms state the requirement inside the seller dashboard with no public page to cite. Those are recorded from the dashboard and the closest public page is listed as the source.
- 3. Agencies and industry roundups
- A few platforms, mainly ones that treat the seller center as the only source of truth, publish no public spec document at all. For those, the numbers come from platform agencies, agencies that manage stores, or industry publications. They are labeled as such so you can see at a glance that they are not first-party.
The real breakdown right now: of 18 platforms, 5 cite the platform own domain and 13 come from agencies or roundups. 51 specs are listed in total, drawn from 13 distinct source domains:
zhuanlan.zhihu.com· 4amz123.com· 2shuaishou.com· 2blog.csdn.net· 1cifnews.com· 1help.shopify.com· 1help.youzan.com· 1kchuhai.com· 1rulechannel.1688.com· 1school.jinritemai.com· 1sellercentral.amazon.in· 1store.weixin.qq.com· 1toutiao.com· 1
Every spec page shows its source domain and the date it was last checked. Both are generated from the data file, not typed by hand.
What this site will not claim
- No "official", no "100% accurate", no "number one". The numbers are a careful reading of public material, and when a platform changes a rule I do not always hear about it first.
- No accounts. Nothing to sign up for, no store details collected.
- No uploads. Every pixel is processed with canvas APIs inside your tab, and no file is sent anywhere.
- No invented contact details. The support address in the footer is real, reaches a person, and is the same one every page lists.
When your seller center disagrees
Trust the seller center. It is the platform talking to you directly, and it is always newer than anything a third party collected. This site is here to get you close quickly and to flag the usual traps, not to replace the source.
Support email: 19211363741@163.com. Write there for anything about the tool, a spec that looks wrong, or a license that will not activate. It is read by one person, so replies usually take a day or two.
If you find a spec that conflicts with what your dashboard shows, publish with the dashboard number. Keep the correction somewhere and send it to that address.
Support and billing
Support email: 19211363741@163.com. This is the address a customer can reach; it is listed on every page footer as well.
Billing questions go to Creem, who is the merchant of record for every purchase. Your receipt comes from Creem and includes an order reference; that reference is also what identifies your license if something goes wrong.
For anything about the tool itself, the fastest path is to reproduce it locally: open your browser developer tools, watch the network panel while you process images, and compare what you see with what the privacy page describes.
Disclaimer
Every size, ratio, and file limit on this site is a reference value. The current notice in your platform seller center always wins. This site is not responsible for a listing that is rejected because its images were prepared from these numbers.