# Symmetric List Creator

## World's Simplest List Tool

This is a super simple browser-based application that turns any list into a symmetric list. As soon as you load your list into the input area, you will get a symmetric list in the output. The items will be copied from the original list so that the new list has the same elements going both directions (left to right and right to left). You can switch between three symmetry modes and remove empty list items. You can also use different list formats and customize the input and output separators of items. Created by list geeks from team Browserling.

Tool Options

#### Item Delimiting Symbol

If delimiter is a single character,
separate the items with it.
If delimiter is multiple characters,
specify the appropriate regexp.
Set the character or regular
expression.

#### List Symmetry Type

For example:
"a, b, c" → "a, b, c, c, b, a".
For example:
"a, b, c" → "a, b, c, b, a".
For example:
"a, b, c, b" → "a, b, c, b, a".

#### Symmetric List Options

Set this separator character
for the symmetric list.
Avoid empty items in the
symmetric list.

## What Is a Symmetric List Creator?

This online utility creates symmetrical lists. A symmetrical list is also known as a palindromic list. Such lists can be read from the beginning to end and from the end to beginning and in both directions they will have the same items. For example, a list "x, y, z, y, x" is a palindromic list because it has the same items from the beginning and end. Here's a more detailed example. If you have another list "a, b, b", then this program makes it symmetrical by adding as many items as required to form symmetry. There are several symmetry types possible for this list. The first one is called mirror symmetry and it duplicates absolutely all the items of the given list in reverse order. In this case, the mirror-symmetric list would be "a, b, b, b, b, a" (the underlined items are the added items, which are the reversed original list). The second type is called centered symmetry. In this case, all the items except the last one are duplicated and the last one is the only item without a matching pair. In this symmetry mode, the list looks like this "a, b, b, b, a" (the underlined items are the new added items that form a symmetric list). The third type of symmetry is called minimal symmetry. When this type is used, the application creates symmetry by trying to add the minimum number of possible items to the list. Here, we get the following list: "a, b, b, a" (only one underlined item had to be added to form a symmetric list). You can create all these symmetry types from any list of any format. You just need to specify which item separator is used in the list. If it is a regular character (such as a comma, a space, or a semicolon), you can specify it in the options. If it is several different characters (such as space and a newline, or a comma and a semicolon), you can match them using a regular expression. Also, you can specify a new separating symbol for the symmetric list and ignore empty items when forming a symmetric list. Listabulous!

## Symmetric List Creator Examples

Click to try!
click me

### Create a Centered Symmetry

In this example, we create a symmetric list from Unicode blocks. The input blocks are placed in order from the smallest to largest and they are separated by a space character. Therefore, we specify the input item separator character to be a space and we select the centered symmetry mode. As a result, the last (tallest block) remains in the center and all other blocks are duplicated in reverse order, creating a symmetric wave.

▁ ▂ ▃ ▄ ▅ ▆ ▇ █
▁ ▂ ▃ ▄ ▅ ▆ ▇ █ ▇ ▆ ▅ ▄ ▃ ▂ ▁
Required options
These options will be used automatically if you select this example.
If delimiter is a single character,
separate the items with it.
Set the character or regular
expression.
For example:
"a, b, c" → "a, b, c, b, a".
Set this separator character
for the symmetric list.
Avoid empty items in the
symmetric list.
click me

### Mirror a List of Greek Letters

In this example, we load a list of Greek uppercase letters and make the list symmetrical. The letters use various delimiters, including spaces, tabs, and newlines. With the help of a regular expression "/\s+/", we are able to match all these whitespace delimiters and split the list into individual letters. Next, we create a mirrored symmetry list where every item has a duplicate (starting from Ω and going backward).

Α Β Γ Δ Ε Ζ Η Θ Ι Κ Λ Μ Ν Ξ Ο Π Ρ Σ Τ Υ Φ Χ Ψ Ω
Α Β Γ Δ Ε Ζ Η Θ Ι Κ Λ Μ Ν Ξ Ο Π Ρ Σ Τ Υ Φ Χ Ψ Ω Ω Ψ Χ Φ Υ Τ Σ Ρ Π Ο Ξ Ν Μ Λ Κ Ι Θ Η Ζ Ε Δ Γ Β Α
Required options
These options will be used automatically if you select this example.
If delimiter is multiple characters,
specify the appropriate regexp.
Set the character or regular
expression.
For example:
"a, b, c" → "a, b, c, c, b, a".
Set this separator character
for the symmetric list.
Avoid empty items in the
symmetric list.
click me

### Minimal Symmetry List

In this example, we create symmetry from a list of classical elements. Some of the words are already duplicated in the list, so we don't have to copy all the items to create symmetry. We split the items by newline, remove empty items, and apply the minimal symmetry method. As a result, only the first two items had to be added in reverse order to the list to make it symmetric.

Fire Air Water Earth Water
Fire Air Water Earth Water Air Fire
Required options
These options will be used automatically if you select this example.
If delimiter is a single character,
separate the items with it.
Set the character or regular
expression.
For example:
"a, b, c, b" → "a, b, c, b, a".
Set this separator character
for the symmetric list.
Avoid empty items in the
symmetric list.

### Pro tipsMaster online list tools

You can pass input to this tool via ?input query argument and it will automatically compute output. Here's how to type it in your browser's address bar. Click to try!

https://onlinetools.com/list/create-symmetric-list?input=%E2%96%81%20%E2%96%82%20%E2%96%83%20%E2%96%84%20%E2%96%85%20%E2%96%86%20%E2%96%87%20%E2%96%88&string-separator=true&input-separator=%20&join-character=%20&centered=true&skip-empty=false

### All List Tools

Quickly print all distinct items of a list.
Quickly print all repeating items of a list.
Quickly count the number of items in a list.
Quickly display list items in multiple colors.
Quickly generate a list of arbitrary length with arbitrary items.
Quickly generate a random length list with random items.
Quickly find certain items in a list.
Quickly find how many times each item appears in the list.
Quickly replace certain items in a list with new items.
Quickly remove items from a list that match a pattern.
Quickly print all list items in reverse order.
Quickly sort list items alphabetically or numerically.
Quickly shuffle list items and make it random.
Quickly randomly pick one or more items from a list.
Quickly set a new delimiter for items in a list.
Quickly remove the symbol that separates list items.
Quickly change list item delimiters to the same symbol.
Quickly remove items from the beginning or end of a list.
Quickly join all items of a list together.
Quickly create groups of multiple list items.
Quickly extract a part of a list.
Quickly remove all empty items from a list.
Quickly remove whitespace characters around list items.
Quickly create multiple copies of a list.
Quickly rotate list items to the left or right (or up and down).
Quickly enumerate list items and add a counter to them.
Quickly add bullet markers to all items in a list.
Quickly remove all bullet markers from list items.
Quickly wrap all list items in quotes.
Quickly remove all quotation marks from around list items.
Quickly add text on the left and right sides of all list items.
Quickly remove text from the left and right sides of all list items.
Quickly prepend a prefix before each list item.
Quickly delete any prefix from the beginning of all list items.
Quickly append a suffix after each list item.
Quickly delete any suffix from the end of all list items.
Quickly add or remove list items to make it a certain length.
Quickly create multiple columns from a single list.
Quickly create a palindromic list from the given list.
Quickly add new items at the beginning or end of a list.
Quickly left-pad a list with one or more items.
Quickly right-pad a list with one or more items.
Quickly remove items that repeat in a list.
Quickly apply a filter on all list items (extract certain items).
Quickly analyze a list and print its item statistics.

### Coming Soon

These list tools are on the way!
Edit a List

View and edit lists in a neat browser-based list editor.

Split a List

Split list items into chunks.

Generate the Powerlist

Create the powerlist of the given list.

Find the Car of a List

Extract the first item from a list.

Find the Cdr of a List

Extract all items except the first of a list.

Apply a Function on a List

Run a JavaScript function on every list item (map function).

Reduce a List

Run the reduce function on a list.

Find Certain List Items

Quickly find and print items that interest you in a list.

Find Repeating List Items

Quickly find and print items that repeat in a list.

Delete Unique List Items

Quickly find and remove items that are unique in a list.

Extract a Sublist from a List

Given start and stop indexes, extract a sublist from a list.

Shift List Items

Shift list items to the left or right (or up and down).

Indent List Items

Add indentation to all list items.

Skew List Items

Make a list go increasingly sideways (to the left or right).

Mirror a List

Quickly create a mirror copy of a list.

Invert a List

Invert the order of items in a list (last becomes first, etc).

Convert a List to Rows

Create multiple rows from a single list.

Convert a List to Excel

Create an Excel (XLS/XLSX) file from a list.

Convert a List to PDF

Create a PDF file from a list.

Convert a Text List to a LaTeX List

Create a LaTeX list from a regular text list.

Convert a Text List to a HTML List

Create a HTML list from a regular text list.

Convert a Text List to a Markdown List

Create a Markdown list from a regular text list.

Compare Two Lists

Find the difference between two lists.

Compare Three Lists

Find the difference between three lists.

Remove One List from Another

Remove elements from a list that appear in the other list.

Find Common Items in Lists

Find items that are shared between two or more lists.

Find Distinct Items in Lists

Find items that are unique in two or more lists.

Zip Two Lists

Join two or more lists together item by item.

Unzip Two Lists

Split an interleaved list into two or more separate lists.

Merge Two Lists

Append a second list at the end of the first list.

Pair List Items

Create pairs from all list items.

Pop List Items

Remove list items at certain index positions.

Push List Items

Add new items at the end of a list.

Splice a List

Modify a list in-place by adding, replacing, or removing items.

Flatten a List

Remove all indentation levels from a list and make it flat.

Make List Items Bold

Quickly apply the bold effect to all list items.

Make List Items Italic

Quickly apply the italic effect to all list items.

Make List Items Cursive

Quickly rewrite all list items in cursive.

Change List Item Font

Quickly change the font of all list items.

Add an Underscore to List Items

Quickly add an underscore to all list items.

Add a Strikethrough to List Items

Quickly add a strikethrough to all list items.

Make List Items Title Case

Quickly change the letter case of all items to title case.

Make List Items Proper Case

Quickly change the letter case of all items to proper case.

Make List Items Random Case

Quickly randomly change the letter case of all items.

Make List Items Lowercase

Quickly change the letter case of all items to small letters.

Make List Items Uppercase

Quickly change the letter case of all items to capital letters.

Remove List Item Counter

Quickly remove any numeration from a list of items.

Create an Empty List

Generate a list with no items (just bullet points).

Visualize a List

Quickly create a graphical representation of a list.

Create a List Cloud

Create an image with a cloud of list items.

Create a Spiral List

Create an image with list items going in a spiral.

Create a ZigZag List

Make list items go in a zigzag.

Add errors and corruption to a list.

Base64-encode a List

Convert any list to base64 encoding.

Base64-decode a List

Convert any list from base64 encoding back to a list.

URL-encode a List

Convert any list to URL encoding.

URL-decode a List

Convert any list from URL encoding back to a list.

Convert a List to JSON

Create a JSON array from a list.

Convert JSON to a List

Create a list from a JSON array.

Convert a List to XML

Create an XML document from a list.

Convert XML to a List

Create a list from an XML document.

Convert a List to YAML

Create a YAML file from a list.

Convert YAML to a List

Create a list from a YAML file.

Convert a Text List to a Binary List

Create a binary list from a text list.

Convert a Binary List to a Text List

Create a text list from a binary list.

Compress a List

Compress a list so it uses less space.

Scroll a List

Create an animation with a list being scrolled.

Let Zalgo Destroy a List

Let Zalgo loose on a list and create list-chaos.

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