Is my input uploaded?

No. The formatter is a hand-rolled JavaScript module that runs in your browser. Use it freely on internal docs or unpublished spec tables.

Which table syntax is supported?

Standard GitHub Flavored Markdown (GFM) `| col | col |` tables. A separator row (`| --- | --- |`) is required. Alignment markers `:---` (left), `:---:` (center), `---:` (right) are honored. Leading / trailing `|` may be omitted; the output normalizes to a consistent form.

Why have a Compact mode?

Useful for posting tables into GitHub Issues / comments where you want minimal character count. It strips all padding to the shortest valid form (`| a | b |`).

Why don't Japanese columns line up?

This tool counts CJK Unified, Hiragana, Katakana, and Fullwidth characters as width 2. Check in a monospace font with CJK support (BIZ UDPGothic, IBM Plex Mono CJK, etc.). Proportional fonts can still look misaligned.

How does the alignment option work?

"Preserve" leaves the original `:---` `:---:` `---:` markers untouched. "Left / Center / Right" overwrites the alignment for every column. To set per-column alignment, edit the output by hand after formatting.

Back to Developer

Markdown Table Formatter

Reformat Markdown tables: pad columns for readability (pretty) or strip padding (compact). Optionally override alignment (left / center / right) for all columns. CJK characters are treated as width 2. Runs entirely in your browser — no uploads.

developerMarkdownformat

How to use

Paste Markdown, press Run, and only the table blocks are reformatted — the surrounding paragraphs are kept untouched. Style is "Pretty (pad columns)" or "Compact (minify)". Alignment override (Preserve / Left / Center / Right) rewrites all `:---` `:---:` `---:` markers across the table. CJK characters are treated as width 2 so columns line up in a monospace editor. No third-party libraries, runs entirely in your browser.

FAQ

Is my input uploaded?: No. The formatter is a hand-rolled JavaScript module that runs in your browser. Use it freely on internal docs or unpublished spec tables.
Which table syntax is supported?: Standard GitHub Flavored Markdown (GFM) `| col | col |` tables. A separator row (`| --- | --- |`) is required. Alignment markers `:---` (left), `:---:` (center), `---:` (right) are honored. Leading / trailing `|` may be omitted; the output normalizes to a consistent form.
Why have a Compact mode?: Useful for posting tables into GitHub Issues / comments where you want minimal character count. It strips all padding to the shortest valid form (`| a | b |`).
Why don't Japanese columns line up?: This tool counts CJK Unified, Hiragana, Katakana, and Fullwidth characters as width 2. Check in a monospace font with CJK support (BIZ UDPGothic, IBM Plex Mono CJK, etc.). Proportional fonts can still look misaligned.
How does the alignment option work?: "Preserve" leaves the original `:---` `:---:` `---:` markers untouched. "Left / Center / Right" overwrites the alignment for every column. To set per-column alignment, edit the output by hand after formatting.

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