datacleaningtools.com staff
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Why VLOOKUP Fails: 6 Messy-Data Causes and the Fix for Each
VLOOKUP returns #N/A on values that look identical because they are not identical: a trailing space, a number stored as text, or a curly quote makes Excel see two different values. The fix is almost never the formula; it is the data. Here are the six causes ranked by how often they bite, with the
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How to Clean an Email List in a Spreadsheet
Cleaning an email list in a spreadsheet takes four passes: lowercase and trim every address, flag structurally invalid ones (no @, spaces, doubled dots), remove duplicates, and only then worry about deliverability, which a spreadsheet cannot test. Here is each pass with the exact formulas, and what honestly requires an email verification service. Pass 1:
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How to Remove Duplicates in Excel Without Losing Good Data
To remove duplicates in Excel safely: normalize the data first (trim whitespace, fix capitalization), use conditional formatting or COUNTIF to SEE the duplicates, then run Data > Remove Duplicates on a copy. Running Remove Duplicates first, on messy data, is the most common way to miss real duplicates, because Excel only matches exact values. Why
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Why Dates Sort Wrong in Excel (and How to Fix Them)
Dates sort wrong in Excel because some of your “dates” are real date values and some are text that only looks like a date. The fix is converting everything to one true date type, or to the ISO format YYYY-MM-DD, which sorts correctly even as text. Here is how to diagnose which problem you have
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How to Fix Phone Number Formats in a Spreadsheet
To fix inconsistent phone numbers in a spreadsheet, strip every non-digit character, then reapply one display format, usually (555) 123-4567 for US numbers. In Excel that is a nested SUBSTITUTE formula plus TEXT; in our free cleaning tool it happens automatically with a preview of every change. This guide shows both, plus the edge cases
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How to Clean Data in Excel: The Five Problems and Every Fix
Cleaning data in Excel means fixing five things: extra whitespace, inconsistent capitalization, mixed phone and date formats, duplicates, and values stored as the wrong type. You can fix all five with built-in Excel functions, and this guide shows each one, or you can upload your CSV to our free cleaning tool and review the changes