Changing many products at once without touching each one.
THE BUILT-IN BULK EDIT
Products > All Products, tick the products, choose Edit from the bulk actions dropdown, and apply.
You can change price, sale price, stock status, stock quantity, weight, shipping class, visibility and status.
CHANGING PRICES IN BULK
The price fields accept three modes: a new value, an increase or decrease by a fixed amount, or by a percentage. The percentage option is how you apply an across-the-board price change.
Test on two products before applying to two hundred.
QUICK EDIT
Hover a product and choose Quick Edit for a single product without opening the full editor. Faster for one-off changes.
USING EXPORT AND IMPORT INSTEAD
For complex changes, export to CSV, edit in a spreadsheet, and re-import with "Update existing products" ticked. Match on SKU or ID.
This is the practical route for large catalogue changes, but back up first.
WHAT TO WATCH
Bulk edits are immediate and there is no undo. Back up before anything substantial.