Duplicate Lines
Repeats every line twice. Free, instant and 100% private in your browser.
Text Tools Runs in your browser
What does Duplicate Lines do?
Repeats every line twice. Paste your text on the left and NMSnabbit instantly shows the duplicated on the right. For example, “a b” gives “a a b b”. Everything runs locally in your browser — nothing is uploaded, so it stays private and works offline. You can process several values at once and copy the result with one click.
How to use the Duplicate Lines
- 1 Type or paste your text into the input box.
- 2 The duplicated appears instantly in the output box as you type.
- 3 Tip: try the example “a b” to see “a a b b”.
- 4 Click “Copy output” to copy the result.
What you can use it for
- Quickly repeats every line twice without installing anything.
- Checking results while learning or teaching how text and duplicated relate.
- Preparing or debugging data for programming, electronics or homework.
- Working privately when the data shouldn't be uploaded to a server.
Frequently asked questions
How do I use Duplicate Lines?
Paste your text into the input field above. Duplicate Lines runs instantly in your browser and shows the duplicated on the right — no button to press and nothing uploaded.
Is Duplicate Lines free and private?
Yes. Duplicate Lines is completely free with no sign-up, and it runs entirely client-side in your browser, so your data never leaves your device.
Can I process more than one value at once?
Yes. Enter several values separated by spaces or new lines and each one is handled independently, so you can batch-process in a single pass.
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