Extract Substring
「Extract Substring」はテキストと文書に使えるブラウザツールです。入力内容と結果は通常この端末内で処理され、登録は必要ありません。
使い方
使い方
- Enter text up to 100,000 characters.
- Choose the 1-based start position, extraction length, index unit, per-line processing, and optional reversal.
- Extract the substring, review empty or shortened results, then copy it or download a text file.
Defined 1-based range behavior
Start position 1 selects the first unit. Length 0 intentionally returns an empty substring. A range that reaches past the end returns the available remainder, while a start beyond the text returns an empty result. Negative, decimal, or excessively large values are rejected rather than silently changed.
Choose a Unicode index unit
Displayed-grapheme mode uses browser grapheme segmentation so combining marks, flags, emoji modifiers, and ZWJ sequences stay intact. Code-point mode exposes the underlying Unicode scalar sequence and can separate those components. Per-line mode applies the same range independently to every LF-separated line and preserves empty lines; optional reversal uses the selected unit.
よくある質問
あわせて知りたいこと
Why is the first position 1 instead of 0?
The user-facing range is deliberately 1-based: position 1 means the first selected unit. The result message repeats the position and unit used.
What happens when the requested length is too large?
The tool returns every available unit from the start position to the end. It does not add padding.
Can this split an emoji?
Displayed-grapheme mode keeps a visible emoji sequence together. Code-point mode can expose and separate the code points inside a flag, modifier sequence, or joined emoji.