How to duplicate a whole line in Vim?

yy or Y to copy the line (mnemonic: yank)
or
dd to delete the line (Vim copies what you deleted into a clipboard-like "register", like a cut operation)

then

p to paste the copied or deleted text after the current line
or
Shift + P to paste the copied or deleted text before the current line

Normal mode: see other answers.

The Ex way:

• :t. will duplicate the line,
• :t 7 will copy it after line 7,
• :,+t0 will copy current and next line at the beginning of the file (,+ is a synonym for the range .,.+1),
• :1,t$ will copy lines from beginning till cursor position to the end (1, is a synonym for the range 1,.).

If you need to move instead of copying, use :m instead of :t.

This can be really powerful if you combine it with :g or :v:

• :v/foo/m$ will move all lines not matching the pattern “foo” to the end of the file.
• :+,$g/^\s*class\s\+\i\+/t. will copy all subsequent lines of the form class xxx right after the cursor.

Reference: :help range, :help :t, :help :g, :help :m and :help :v

YP or Yp or yyp.

Doesn't get any simpler than this! From normal mode:

yy

then move to the line you want to paste at and

p

yy

will yank the current line without deleting it

dd

will delete the current line

p

will put a line grabbed by either of the previous methods

Do this:

First, yy to copy the current line, and then p to paste.

If you want another way:

"ayy: This will store the line in buffer a.

"ap: This will put the contents of buffer a at the cursor.

There are many variations on this.

"a5yy: This will store the 5 lines in buffer a.

See "Vim help files for more fun.

yyp - remember it with "yippee!"

Multiple lines with a number in between:

y7yp

yyp - paste after

yyP - paste before

I like: Shift+v (to select the whole line immediately and let you select other lines if you want), y, p

Another option would be to go with:

nmap <C-d> mzyyp`z

gives you the advantage of preserving the cursor position.

You can also try <C-x><C-l> which will repeat the last line from insert mode and brings you a completion window with all of the lines. It works almost like <C-p>

For someone who doesn't know vi, some answers from above might mislead him with phrases like "paste ... after/before current line".
It's actually "paste ... after/before cursor".

yy or Y to copy the line
or
dd to delete the line

then

p to paste the copied or deleted text after the cursor
or
P to paste the copied or deleted text before the cursor

For more key bindings, you can visit this site: vi Complete Key Binding List

I know I'm late to the party, but whatever; I have this in my .vimrc:

nnoremap <C-d> :copy .<CR>
vnoremap <C-d> :copy '><CR>

the :copy command just copies the selected line or the range (always whole lines) to below the line number given as its argument.

In normal mode what this does is copy . copy this line to just below this line.

And in visual mode it turns into '<,'> copy '> copy from start of selection to end of selection to the line below end of selection.

I prefer to define a custom keymap Ctrl+D in .vimrc to duplicate the current line both in normal mode and insert mode:

" duplicate line in normal mode:
nnoremap <C-D> Yp
" duplicate line in insert mode:
inoremap <C-D> <Esc> Ypi

Default is yyp, but I've been using this rebinding for a year or so and love it:

" set Y to duplicate lines, works in visual mode as well. nnoremap Y yyp vnoremap Y y`>pgv

1 gotcha: when you use "p" to put the line, it puts it after the line your cursor is on, so if you want to add the line after the line you're yanking, don't move the cursor down a line before putting the new line.

For those starting to learn vi, here is a good introduction to vi by listing side by side vi commands to typical Windows GUI Editor cursor movement and shortcut keys. It lists all the basic commands including yy (copy line) and p (paste after) or P(paste before).

vi (Vim) for Windows Users

If you would like to duplicate a line and paste it right away below the current like, just like in Sublime Ctrl+Shift+D, then you can add this to your .vimrc file.

nmap <S-C-d> <Esc>Yp

Or, for Insert mode:

imap <S-C-d> <Esc>Ypa

I like to use this mapping:

:nnoremap yp Yp

because it makes it consistent to use alongside the native YP command.

I use this mapping, which is similar to vscode. I hope it is useful!!!.

nnoremap <A-d> :t. <CR>==
inoremap <A-d> <Esc>:t. <CR>==gi
vnoremap <A-d> :t$ <CR>gv=gv

If you want to duplicate a line just below, the answers above are correct.

Another common case would be if you are somewhere in your text, and you want to duplicate a line located far away in your buffer, out of sight, and you don't want to go there, for some reason.

In this case:

• begin typing a few letters of the beginning of the line that you want to duplicate;
• hit Ctrl-X Ctrl-L: this will bring a pop-up list similar to the autocompletion one (Ctrl-P and Ctrl-N);
• navigate up and down through this list with Ctrl-L and Ctrl-N until you get the line you wish;
• hit Enter, and voilà.

I find this particularly handy when you write code.