Merge two Markdown tables on a key column. Inner, left, or outer joins — like SQL, but for Markdown.
Both inputs must contain at least one Markdown table.
Free Markdown Table Merger joins two GFM pipe tables on a shared key column — SQL-style, but for Markdown. Pick inner, left, or outer join, specify the key column index in each table, and get one combined table with all non-key columns side-by-side.
Privacy: This tool runs entirely in your browser. Your text is never uploaded, logged, or cached. Close the tab and it's gone. Verify in DevTools → Network: zero requests fire.
Joining two Markdown tables manually means copying, matching rows by eye, and fixing pipes. That's 15 minutes per merge. This runs locally in under 50 ms, returns a pretty-printed result, and is free forever.
| Input | Output | Typical size | Speed | Login needed |
|---|---|---|---|---|
| Two GFM tables (Markdown) | Merged Markdown table | Up to 5 MB each | < 50 ms | No |
Here's what this free tool does in detail — every feature is built to solve real problems, runs entirely in your browser, and is free forever.
Three join types, just like SQL: Inner returns only rows where the key matches in both tables. Left keeps every row from Table A and fills Table B columns with blanks (or your custom value) for unmatched keys. Outer keeps every row from both tables, using fills for both sides.
Pair with the Free Markdown Table Sorter to order the merged result, or the Free Markdown Table Transposer to reshape it.
The key column doesn't have to be in the same position in both tables. Set Key col A and Key col B independently (0-based index). The join-key column appears once in the merged table, followed by every other column from A and every other column from B.
For non-table joins, try the Free CSV to Markdown Table to bring external data in first.
Left and outer joins produce empty cells for unmatched rows. By default these are blank strings, but you can customize with the Fill missing field — set it to N/A, —, 0, or anything else. Useful when you want visual consistency or strict non-null cells.
The merged table uses auto-aligned column widths so every column lines up in the raw Markdown source. Great for committing to git, where alignment makes diffs easier to read. The separator row grows to match the widest cell in each column.
For broader markdown cleanup, try the Free Markdown Formatter.
Drop Table A in the left box and Table B in the right box. Each must be a valid GFM pipe table with a header row.
Key col A and Key col B define which columns match. Pick inner, left, or outer. Add a fill value if you want non-blank cells for missing matches.
The result is a single table with all non-key columns from both sides, pretty-printed for readability.
Join user metadata from one source with activity counts from another, all in Markdown.
Merge a dependency table with license information from a separate audit report.
Join roster tables with task assignments for a status report, all without leaving Markdown.
Join product feature and pricing tables for an at-a-glance comparison.
Merge participant demographics with response data into one publishable table.
Yes. Free forever, no account required.
Inner, left, and outer. Inner returns only matching rows, left keeps all of Table A, outer keeps all rows from both.
Yes. Duplicate keys in either table produce multiple output rows (one per combination), like SQL does.
The join uses an in-memory hash index and runs in O(n+m) time. Tables with thousands of rows merge in under 50 ms.
No. Runs 100% in your browser.