> ## Documentation Index
> Fetch the complete documentation index at: https://docs.markifact.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Merge Lists

> Combine multiple lists into a single unified list for streamlined processing.

**Merge Lists** takes multiple separate lists and combines them into one unified list. Essential for consolidating data from different sources, combining campaign results, or preparing merged datasets for processing.

***

## When to Use It

* Combine campaign lists from different advertising platforms
* Merge client data from multiple spreadsheets
* Consolidate URL lists from various sources
* Unify keyword lists before processing

***

## Inputs

| Field              | Type           | Required | Description                                          |
| ------------------ | -------------- | -------- | ---------------------------------------------------- |
| **Lists to Merge** | Multiple Lists | Yes      | Add multiple lists that you want to combine into one |

***

## Outputs

| Output          | Description                                           |
| --------------- | ----------------------------------------------------- |
| **Merged List** | Single list containing all items from the input lists |

***

## Credit Cost

Free to use - no credits required.

***

## How It Works

Takes multiple lists and combines them in the order you provide them:

**Example:**

```
List 1: ["Campaign A", "Campaign B"]
List 2: ["Campaign C", "Campaign D"] 
List 3: ["Campaign E"]
Merged Result: ["Campaign A", "Campaign B", "Campaign C", "Campaign D", "Campaign E"]
```

Items are added in sequence - first all items from List 1, then all from List 2, and so on.

***

## Real-World Examples

**Unified Cross-Platform Reporting:**

```
Google Ads Get Report (campaign performance data) → List 1
Meta Ads Get Report (campaign performance data) → List 2
LinkedIn Ads Get Report (campaign performance data) → List 3
→ Merge Lists → Write to Sheets
"Create one master report with all platform data in a single table"
```

***

## Best Practices

**Order Matters:**

* Lists are merged in the order you add them
* First list items appear first in the merged result
* Consider priority when arranging your lists

**Data Consistency:**

* Ensure all lists contain similar types of data
* Mixed data types work but may complicate later processing
* Consider standardizing formats before merging

**Post-Merge Processing:**

* Often useful to use Remove Duplicates after merging
* Count List Items to verify expected total
* Consider splitting large merged lists for processing

***

## FAQ

<Accordion title="Does merging preserve the order of items?">
  Yes, items maintain their order within each list, and lists are combined in the sequence you provide them. List 1 items come first, then List 2 items, etc.
</Accordion>

<Accordion title="What happens if I merge lists with duplicate items?">
  Duplicates are preserved in the merged list. If List 1 has "Campaign A" and List 2 also has "Campaign A", the merged list will contain both. Use Remove Duplicates afterward if needed.
</Accordion>

<Accordion title="Can I merge lists with different data types?">
  Yes, you can merge lists containing different types of data (text, numbers, etc.). However, ensure your downstream processing can handle the mixed data types appropriately.
</Accordion>

<Accordion title="Is there a limit to how many lists I can merge?">
  You can add multiple lists to merge. The practical limit depends on your system's memory and the size of the individual lists being combined.
</Accordion>

<Accordion title="What if one of my lists is empty?">
  Empty lists are handled gracefully - they simply don't contribute any items to the merged result. The merge will continue with the non-empty lists.
</Accordion>

<Accordion title="How is this different from using multiple nodes separately?">
  Merging creates a single list that can be processed as one unit in subsequent nodes like Loop Over List, whereas separate lists would require separate processing chains.
</Accordion>

<Accordion title="Should I remove duplicates before or after merging?">
  Usually after merging, as you want to see the full scope of duplicates across all your source lists. Removing duplicates before merging might miss cross-list duplicates.
</Accordion>