# Join Array

Join array items into a single string with a custom separator

> Canonical page: https://elysiatools.com/en/tools/join-array

- **Category:** Data Processing

- **Keywords:** array, join, string, separator, combine

## Overview

Join array items into a single string using a custom separator.

**Highlights:**
- Accepts a JSON array
- Uses the separator exactly as provided
- Objects/arrays are JSON-stringified before joining

**Example:**
- Array: `["a", "b", "c"]`
- Separator: `-`
- Result: `a-b-c`

## Inputs

- **Array** (textarea): Enter a JSON array
- **Separator** (text): String placed between items

## When to use

- When you need to combine array elements into a comma-separated string for reports or exports.
- When preparing list data for display in user interfaces, logs, or documents.
- When converting structured JSON arrays into plain text for APIs or data processing pipelines.

## How it works

- Input a valid JSON array into the 'Array' field, such as \["item1", "item2"\].
- Specify a custom separator in the 'Separator' field; it defaults to a comma and space (", ").
- The tool processes each element, converting objects or arrays to JSON strings as needed.
- It outputs a single string with all elements joined by the provided separator.

## Use cases

- Generating CSV-like strings from array data for spreadsheet imports or data exports.
- Formatting lists for readable output in web applications, reports, or terminal displays.
- Preparing array data as a single string for APIs, configuration files, or logging systems.

## Frequently asked questions

### What format must the array input be in?

The array must be in valid JSON format, like ["value1", "value2"].

### Can I use special characters or an empty string as the separator?

Yes, the separator can be any string, including special characters or an empty string for direct concatenation.

### How are non-string elements like numbers or objects handled?

Non-string elements are converted to strings; objects and arrays are JSON-stringified before joining.

### Is there a limit on the array size or number of elements?

The tool supports arrays of typical sizes, but very large arrays may affect performance.

### What is the default separator if none is provided?

The default separator is a comma followed by a space (", ").

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