Find out why your Google Sheets™ spreadsheet is slow. Sheet Speed Checker looks at your spreadsheet — empty rows past the data, imports from other files, volatile formulas, conditional-format clutter, lookups over whole columns — and shows you where the time goes, ranked by estimated cost. Each finding explains itself in plain words and links to a guide section with the manual fix. Checking the active sheet is free and unlimited. Pro fixes the safe ones in one click: trimming empty grid, calming recalculation, freezing finished imports and volatiles to values, merging fragmented format rules. Every fix previews exactly what changes and takes a restore point first, and Undo is free forever. Nothing in your spreadsheet leaves Google™. The add-on reads formulas only, can reach only the spreadsheet it is opened in, and its only network traffic is a licence check. Google™, Google Sheets™ and Google Workspace™ are trademarks of Google LLC™. Sheet Speed Checker is not affiliated with or endorsed by Google™.