Remove Duplicate Columns from Excel in 1 Click — Free, No Upload, Data Safe
Match columns by header name or identical values, keep the first occurrence, and review a per-sheet report. No upload, no signup.
Drop one .xlsx, .xlsm, or .xls file here, or click to browse
Supports .xlsx / .xlsm / .xls · processed locally · never uploaded
Two Detection Modes: Header Name vs Column Values
| By header name | By column values | |
|---|---|---|
| What is compared | First-row header text, trimmed | Every participating cell in the column |
| Best for | Repeated labels after VLOOKUP or merged tables | The same data copied into two columns |
| Sensitivity | Case-sensitive: Name and name differ | Type-sensitive: the number 1 differs from "1" |
| Blanks | Columns with empty headers are always kept | Consecutive fully empty columns collapse into the first one |
In both modes the first occurrence is kept and later duplicates are deleted, and surviving columns keep their original order — columns are never reordered.
How to Remove Duplicate Columns Online
- Drop one .xlsx, .xlsm, or .xls workbook — it is processed locally and never uploaded.
- Pick a mode: “Same header name” compares first-row labels; “Identical column values” compares the data.
- In values mode, keep “First row is a header” checked (the default) so header text is excluded and only data rows are compared.
- Click Remove duplicate columns — every sheet is scanned and a before→after report is shown per sheet.
- Download the clean .xlsx named your-file-name-no-duplicate-columns.xlsx.
When You Need This
- Several VLOOKUP formulas each pulled the same field, leaving repeated ID or name columns.
- Two tables were merged or joined side by side and the join key now appears more than once.
- A database or CRM export contains the same metric under two header labels.
- Copied-paste edits duplicated a whole column of data.
- Empty spacer columns pile up between imported fields and you want to collapse them.
How Empty Columns Are Treated
In values mode, fully empty columns are considered identical to each other: when several empty columns sit next to one another, only the first is kept and the rest are removed. In header mode, columns with blank or empty header labels never participate in comparison and are always kept — even if their data is identical. Choose the mode that matches the result you want.
The output is a value-level .xlsx rebuilt from your data: cell styles, column widths, merged cells, and charts are simplified. Formulas are written out as their cached values.
Need to Remove Duplicate Rows Instead?
This tool deletes repeated columns (vertical fields). If your problem is repeated rows — the same record appearing two or more times — use the companion Remove Duplicate Rows tool at /remove-duplicates-from-excel, which compares whole rows and keeps the first occurrence. Many cleaning workflows use both: columns first, then rows.
Frequently Asked Questions
Is this duplicate-column remover free?
Yes — completely free, with no sign-up, no watermark, and no file limit. All processing happens in your browser.
How does header-name mode decide what is duplicate?
Header labels are converted to text and trimmed before comparison, which is case-sensitive: “Name” and “name” stay as two columns, while “ Name ” matches “Name”. Columns with blank or empty headers are never compared and are always kept.
What does the column-values mode compare?
Each column is reduced to the values of its participating rows (data rows when the header option is on). Values are normalized — dates become ISO timestamps, empty cells become null — then serialized. Comparison is type-sensitive, so the number 1 and the text "1" are not duplicates.
Will it delete my empty columns?
In values mode, consecutive fully empty columns are considered identical and only the first is kept. In header mode, columns with empty header labels are always kept.
Is my formatting preserved?
No — the file is rebuilt from cell values, so styles, column widths, merged cells, and charts are simplified and formulas become constants. Use the online editor if formatting matters.
Is my file uploaded, and which formats work?
The workbook is parsed and rebuilt entirely in your browser — it never leaves your device. Supported inputs are .xlsx, .xlsm, and legacy .xls; encrypted workbooks cannot be read, and the result is always a modern .xlsx.
Related Tools
Want to inspect the columns before removing them?
Open the free online Excel editor