Why copied web tables arrive broken in Excel
Selecting a table on a page and pasting it into a spreadsheet feels like it should work, and it does just often enough to be trusted. The failures are structural, not random, and once you know the three usual causes the cleanup stops being a surprise.
Cause one: the table is not a table
Plenty of pages that look tabular are built from divs, styled to resemble rows and columns. There is no cell structure to copy, so the clipboard receives a run of text and the spreadsheet guesses where columns should be. If selecting a row highlights the whole row as one block, you are almost certainly looking at a div grid.
Cause two: merged and nested cells
A header cell spanning three columns, or a cell that contains its own small table, breaks the rectangle a spreadsheet expects. Paste it and values shift one column to the right for every row after the merge. The data is not wrong; it has been placed according to a structure the target file cannot represent.
Cause three: hidden content
Responsive tables often duplicate their content, once for wide screens and once for narrow ones, hiding whichever version does not apply. Copy the page and you can capture both, so every row appears twice. Sorting afterwards puts the duplicates next to each other, which is the first time most people notice.
What a clean export does instead
Reading the table structure directly and writing a real spreadsheet avoids all three. Cells are addressed by row and column, spans are resolved deliberately rather than guessed, hidden duplicates are dropped, and numbers are written as numbers so totals work immediately. The result opens in Excel, Numbers or Google Sheets without a single conversion step.
Check three things before you trust the file
Look at the header row: it should have exactly as many cells as the body. Check the last row against the page, since truncated exports lose the tail. Then try summing a numeric column; if the total comes back as zero, the values were written as text and the export took a shortcut.
