# Zip Arrays

Combine arrays by index using lodash _.zip

> Canonical page: https://elysiatools.com/en/tools/zip-arrays

- **Category:** Data Processing

- **Keywords:** array, zip, group, index, lodash

## Overview

Group elements by index across multiple arrays.

**Highlights:**
- Uses lodash `_.zip`
- Accepts 2-4 JSON arrays
- Missing values are filled with null

**Example:**
- Array 1: `["a", "b"]`
- Array 2: `[1, 2]`
- Result: `[["a", 1], ["b", 2]]`

## Inputs

- **Array 1** (textarea): Enter a JSON array
- **Array 2** (textarea): Enter a JSON array
- **Array 3** (textarea): Optional third array
- **Array 4** (textarea): Optional fourth array

## When to use

- When you need to pair corresponding data points from separate lists into a single structured format.
- When you are preparing data for visualization or API consumption that requires grouped key-value pairs.
- When you need to align datasets of equal or unequal length where missing values should be explicitly marked as null.

## How it works

- Input your primary data arrays into the provided fields, supporting up to four separate JSON arrays.
- The tool processes the inputs by matching elements at each index position across all provided arrays.
- The output generates a nested array where each sub-array contains the elements found at that specific index.
- If one array is shorter than the others, the tool automatically fills the missing positions with null values.

## Use cases

- Merging a list of user IDs with their corresponding email addresses into a single list of pairs.
- Synchronizing timestamp arrays with sensor reading arrays for time-series data analysis.
- Combining product names, prices, and stock quantities into a unified inventory structure.

## Frequently asked questions

### What happens if my arrays have different lengths?

The tool will continue to group elements until the longest array is exhausted, filling any missing indices in shorter arrays with null.

### How many arrays can I zip at once?

You can provide between two and four JSON arrays to be combined simultaneously.

### Is the input format strictly JSON?

Yes, the tool expects valid JSON array syntax, such as ["a", "b"] or [1, 2, 3].

### Does this tool use standard library functions?

Yes, it utilizes the lodash _.zip function to ensure consistent and predictable grouping behavior.

### Can I use this for non-string data?

Yes, the tool supports any valid JSON data types, including numbers, booleans, and strings within your arrays.

## Related tools

- [Count By](https://elysiatools.com/en/tools/count-by): Count items by a derived key using lodash _.countBy
- [Group By](https://elysiatools.com/en/tools/group-by): Group items by a derived key using lodash _.groupBy
- [Index Of](https://elysiatools.com/en/tools/index-of): Find the index of a value in array using lodash _.indexOf
- [Intersection Arrays](https://elysiatools.com/en/tools/intersection-arrays): Find common values across multiple arrays using lodash _.intersection
- [Invert By](https://elysiatools.com/en/tools/invert-by): Invert keys grouped by values using lodash _.invertBy
- [Nth Item](https://elysiatools.com/en/tools/nth-item): Get the item at a specific index using lodash _.nth
- [Remove By Predicate](https://elysiatools.com/en/tools/remove-by-predicate): Remove items that match a predicate using lodash _.remove
- [Sorted Index](https://elysiatools.com/en/tools/sorted-index): Find the insertion index in a sorted array using lodash _.sortedIndex

## Samples

- [ZIP Viewer Samples](https://elysiatools.com/en/samples/zip-viewer-samples): A small ZIP archive with text and JSON files for in-browser preview
- [Grafana Advanced Application Samples](https://elysiatools.com/en/samples/grafana-samples): Comprehensive Grafana samples covering advanced dashboard design, alerting configurations, data source integrations, and plugin development
- [QR Code Samples](https://elysiatools.com/en/samples/qrcode-samples): Sample QR code images for testing QR code reading and generation tools
- [D3.js Data Visualization Samples](https://elysiatools.com/en/samples/d3js-data-visualization): Comprehensive D3.js data visualization examples including charts, maps, animations, and interactive visualizations

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