Tabs to Spaces

About this tool

Tabs to Spaces converts the whitespace in text or code between tabs and spaces — the same job as expand/unexpand — right in your browser. A tab is never a fixed run of spaces: it advances to the next tab stop, the next column that is a multiple of the tab width, so the result stays aligned.

• Direction — expand (default) turns tabs into spaces; unexpand turns runs of spaces back into tabs.
• Tab width — columns per tab stop (1–16, default 4). Common values are 2, 4, and 8 (the Unix default).
• Scope — all converts both leading indentation and inline whitespace; leading touches only the indentation before the first non-blank character on each line and copies the rest verbatim.

Each line is processed independently and existing line breaks are preserved. Everything runs locally via WebAssembly — your text is never uploaded.

Worked example

Expanding this input with tab width 4 and direction expand:

→if (ok) {
→→return 1;
→}

(where → marks a tab) produces spaces to the next tab stop on each line:

    if (ok) {
        return 1;
    }

The first tab (column 0) fills 4 spaces; the doubly-indented line fills 8. A tab placed after ab (column 2) would fill only 2 spaces, because it only needs to reach column 4 — that is what "respecting tab stops" means.

Handy for

• Normalizing a snippet to your project's indentation style before pasting.
• Meeting a linter that requires spaces (or tabs) for indentation.
• Cleaning up mixed tabs and spaces in copied code.

FAQ

Limits & edge cases

• Tab width is clamped to 1–16. A value of 0 becomes 1, and anything above 16 becomes 16.
• Only the tab character (\t) and the space character are treated as whitespace; other Unicode spaces are left as-is and each counts as one column.
• Very large pastes run entirely in your browser, so speed depends on your device — but nothing is ever sent to a server.