01
Choose stack or lookup
Stacking appends every input row to one table. A lookup join keeps the rows from file A and adds matching fields from file B using an ID you select.
Bring separate exports into one useful table.
Combine CSV, TSV and Excel data without copying columns by hand. Stack rows from multiple files, aligning headers by exact name, or enrich a main table from a lookup file.
File contents stay in your browserFree · no account to run or export
A PRACTICAL EXAMPLE
A January export with Order ID and Amount can be stacked with February’s Order ID, Amount and Channel. January rows receive a blank Channel instead of shifting the Amount column.
02
Check column names and IDs
Stacking uses exact header names; Email and E-mail remain separate columns. Lookup IDs use exact text with outer spaces trimmed. Duplicate IDs in the lookup file must be resolved before the join can run.
03
Keep the source references
Add source file, sheet and row columns to stacked data. A lookup can include both main and lookup row numbers. Unmatched main rows are retained with blank lookup fields.
Know what to expect
Stacking does not remove duplicates automatically. The free plan accepts two files and up to 2,000 total input rows per run.
Supports CSV, TSV and unencrypted XLSX, up to 20 MB per file and 100 input columns. Free use includes 2,000 total input rows per run. Excel downloads contain text cells to preserve identifiers such as 00123. Workbook styling and formulas are not retained.
Read the file and export guideClean CSV & Excel files
Trim spaces, remove duplicate rows and standardise selected date and number columns. Download a change report alongside your cleaned data.
Compare Excel & CSV files by ID
Match records using an ID, even when rows move. See added, removed, changed and ambiguous records with their source-row references.
Map & rename CSV columns
Rename, reorder and select columns for an import. Set defaults or constant values, then save the mapping for the next export.