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repeat-string

Repeating a string multiplies it by a chosen count, optionally separated by a delimiter. Useful for generating test data ("aaaa..."), creating dividers ("=====" × 60), padding strings, building progress bars in plain text, and producing fillers for layout tests. The ZTools Repeat String tool runs in the browser and handles up to a few million characters of output.

Use cases​

Generate stress-test inputs​

A function should handle 10,000-char strings; generate "x" repeated 10,000 times to test.

Build a divider line​

"=" × 60 produces a visible separator for log files or terminal output.

Pad a string to fixed width​

Repeat space N times to pad an alignment.

Pattern fillers for layout testing​

"Lorem ipsum" repeated 50 times stress-tests text wrapping.

How it works​

  1. Type the string — Any text including special characters and emoji.
  2. Set count — 1 to ~100,000 (browser memory caps higher).
  3. Optional separator — Empty (default), space, comma, newline, or custom string.
  4. Output — Concatenated result. Length displayed.

Examples​

Input: "abc" × 5

Output: "abcabcabcabcabc" (15 chars).

Input: "=" × 60

Output: A 60-char divider line.

Input: "item" × 3 with separator ","

Output: "item,item,item".

Input: "\n" × 10

Output: 10 blank lines.

Frequently asked questions​

Maximum length?

Browser allows ~100M chars in memory. Practical UI limit is ~1M for paste / display performance.

Unicode-safe?

Yes — emoji and multi-byte characters repeat correctly.

Difference from JavaScript .repeat()?

Same operation. Tool exposes it visually with separator option (which String.prototype.repeat doesn't have).

Privacy?

All in browser.

Tips​

  • For dividers, use repeat-with-separator-newline for vertical bars; repeat-no-separator for horizontal lines.
  • For test inputs, generate at exact target length to test boundary cases (255, 256, 1024, 10000).
  • For Unicode, count by code points if you need exactness — UTF-16 surrogate pairs can confuse "length".

Try it now​

The full repeat-string runs in your browser at https://ztools.zaions.com/repeat-string — no signup, no upload, no data leaves your device.

Open the tool ↗

Last updated: 2026-05-06 · Author: Ahsan Mahmood · Edit this page on GitHub