Text Repeater

The Text Repeater duplicates any text the number of times you specify, joining repetitions with your chosen separator — newline, comma, space, or custom string. Simple feature, surprisingly useful. Generate test data (50 rows of the same row for load testing), create filler content (repeat a paragraph 10 times for CSS layout testing), build quick lists (repeat a label 100 times for a bulk import), stress-test text fields (paste 1000 characters into a form with a 500-character limit to verify error handling), or just save time on any task that involves creating the same string multiple times.

Text can be any length — a single character, a word, a paragraph, or a multi-line block. Repeat count ranges from 2 to 100,000. Separators include newline (one repetition per line), space (words on one long line), comma (a comma-separated list), tab (column-separated), or any custom string you type. Each repetition can optionally be numbered with sequence numbers, useful for generating test data where each row needs a unique identifier. Output copies with one click. All processing runs in your browser so even very long inputs repeated many times never leave your machine.

Text repetition is trivial in principle — construct the output by concatenating N copies of the input with the chosen separator — but implementation details affect performance and usability for large outputs.

Naive implementation: new Array(n).fill(text).join(separator). Works for any n and is O(n×m) where m is text length.

String.prototype.repeat is a JavaScript built-in optimized for character repetition: \"abc\".repeat(3) = \"abcabcabc\". Very fast but does not support a separator — you combine it with join.

Memory limit: very large outputs (a 1000-character string repeated 100,000 times = 100 MB plus separators) can exceed browser tab memory. The tool warns when the estimated output exceeds 50 MB and caps repetition to prevent freezing.

Sequence numbering: when each repetition needs a unique ID, the tool substitutes a placeholder (typically {i} or #) in the input with the current iteration number. Optional zero-padding aligns numbers visually.

Separator handling: the separator goes between repetitions, not at the start or end. A 3-repeat with newline separator produces \"text\\ntext\\ntext\" (two newlines), not \"\\ntext\\ntext\\ntext\\n\" (four newlines).

Performance: 100,000 repetitions of a short string complete in under 100 ms. Larger outputs take proportionally longer, bounded by memory.

Use cases in practice:
- Generate test CSV with repeated rows
- Create spacer text for web layout testing
- Build a bulk list of identical items (like 50 \"pending\" rows)
- Generate repeated characters for visual effects (━━━━━━━━━━)
- Create long strings for buffer overflow or length validation testing

Compared to manually copying and pasting, this tool is vastly faster for any count above 2 or 3. Manual copying is fine for a handful of repetitions; beyond that this tool saves minutes per task.

Compared to a programming language repeat function (Python\u2019s * operator, JavaScript\u2019s .repeat()), this tool is faster for one-off use when you don\u2019t want to open a REPL. For automation in code, use the language built-in.

Compared to a spreadsheet with filled cells, this tool handles multi-line and complex separators that spreadsheet autofill does not. Spreadsheets win for tabular repetition with formulas; this tool wins for plain text.