Insert Text at a Position

Insert Text at a Position adds a string exactly where you specify inside existing text. Provide the original text, the content to add, and a zero-based character position; the result preserves every original character and places the new content between the characters on either side of that index. It is useful for assembling templates, adding labels or separators, correcting generated content, and making precise edits in repeatable workflows. Unicode characters are counted consistently, so emoji and other characters outside the basic Latin alphabet do not unexpectedly consume two positions.

Choose the exact insertion point

Positions are zero-based, which means position 0 inserts before the first character. Position 1 inserts after the first character and before the second, while a position equal to the original text length appends the chosen string at the end. For example, the text Hello world has a space at position 5 and the letter w at position 6.

Inserting beautiful at position 6 produces Hello beautiful world. Nothing is overwritten: the operation splits the original at the requested boundary, places the insertion between the two pieces, and joins them again. This definition makes the operation predictable in scripts and visual editing tools.

A negative position or a value beyond the final boundary is rejected instead of being silently adjusted, preventing an unnoticed edit in the wrong place. The response repeats the applied position and reports original, inserted, and resulting character lengths so an automated workflow can verify what changed.

Work safely with Unicode text

This capability counts Unicode code points rather than JavaScript UTF-16 code units. That distinction matters whenever text contains emoji, historic scripts, or many less common symbols. A character such as an emoji may occupy two internal UTF-16 units, yet it is treated as one position here, so an insertion will not split its surrogate pair and create broken text.

The same counting rule is used for the reported original, inserted, and result lengths. Combining marks and multi-code-point emoji sequences can still contain several code points even when a font displays them as one visual cluster; this is a property of Unicode text rather than an arbitrary adjustment by the tool. If your source positions come from another system, confirm that it also counts Unicode code points.

Byte offsets, UTF-16 indexes, and grapheme-cluster indexes are different coordinate systems. Keeping the coordinate system explicit is especially valuable when templates move between browser code, databases, and backend services, because it prevents subtle position drift and makes repeated transformations produce the same result everywhere.

Build precise templates and editing workflows

Exact insertion is a small operation that becomes powerful when composed with other steps. A document workflow can insert an account name after a fixed greeting, add a tracking token before a file extension, or place a generated clause at a boundary identified by an earlier parser. Because existing text is preserved, this tool differs from replacement: there is no search term to match and no selected range to remove.

It is best when your workflow already knows the intended character boundary. Validate that boundary whenever upstream content can change, since adding or removing characters before it will shift the correct position. For reusable templates, stable markers are often easier to maintain than hard-coded offsets; once a marker has been located, its index can be passed here for the actual insertion.

Empty insertion text is accepted as a deliberate no-op, which can simplify conditional pipelines without special branching. The function is deterministic and uses no network, randomness, or current time, so identical inputs always return identical outputs.