Look it up, don’t guess.
Ecom Almanac is a reference desk, not a magazine. We maintain the tables, codes, size charts, formulas and checklists that people who run online stores keep having to look up: ISO codes, platform image specs, fee math, pre-launch steps. Each page is built to answer one question completely, so you can bookmark it and come back.
Every table states its source and the date we last checked it. When a standard changes, we revise the page and note the revision — we would rather update one page forever than publish a new post nobody can find. Formulas are shown next to their results so you can verify the math yourself.
Read our full editorial policy for sourcing, revisions and funding.
Corrections and table requests: [email protected]