Resize Image in n8n

Resize Image is a PDF4me node action in n8n that scales an image either by a percentage of its original size or to exact pixel width and height, with aspect ratio preservation available as a toggle. Use it to generate thumbnails, normalise user uploads to a house size, or shrink oversized photos before they reach storage.

What this node does

PDF4me: Resize Image takes an image from Binary Data, a Base64 String, or a URL and returns a scaled copy. The Resize Type field decides the method: Percentage scales relative to the original, which suits mixed-size inputs, while Specific targets an exact width and height in pixels for fixed layout slots. Because the node runs once per incoming item, one configured node resizes an entire batch with identical settings.

Authenticating Your API Request

Every PDF4me node in n8n requires a valid Credential to connect with. Create or select one that holds your PDF4me API key so the workflow can authenticate resize requests securely.

Get your API Key

Important Facts You Should Not Miss

Resize Type decides which fields appear

Choosing Percentage reveals Resize Percentage. Choosing Specific reveals Width and Height instead. You never fill in both sets.

Maintain Aspect Ratio prevents distortion

Leave this toggle on unless you deliberately need non-proportional dimensions. With it off, a mismatched width and height will stretch the picture.

Enlarging cannot invent detail

A percentage above 100 increases pixel dimensions but not sharpness. Always start from the highest-resolution source available.

PDF4me node in n8n set to Action Resize Image, Input Data Type Binary Data, Input Binary Field data, Output File Name resize_image_output.jpg, Resize Type Percentage, Resize Percentage 50, with Maintain Aspect Ratio and Async toggles enabled — PDF4me Resize Image parameters panel in n8n, shown in Percentage mode

Percentage vs Specific: Which Resize Type Should You Use?

The two modes solve different problems, and picking the wrong one is the most common source of unexpected output sizes.

Resize Type	Fields you fill in	Best fit
Percentage	Resize Percentage, for example 50 to halve or 200 to double	Mixed-size inputs that should all shrink or grow by the same proportion, keeping their relative differences
Specific	Width and Height in pixels	A fixed layout slot, thumbnail grid, or platform that demands exact dimensions regardless of the source size

What Parameters Does Resize Image Need?

Required: Action, Input Data Type, the field matching that input type, Output File Name, Resize Type, and the dimension fields that Resize Type reveals. Async and Binary Data Output Name carry working defaults.

Parameter	Required	What it does	Example
Action	Required	Selects the PDF4me node action to run. Choose Resize Image.	`Resize Image`
Input Data Type	Required	Format of the source image input. Choose Binary Data (from a previous node), Base64 String, or URL.	`Binary Data`
Input Binary Field	Conditional	Name of the binary property on the incoming n8n item that holds the image. Required when Input Data Type is Binary Data. Defaults to data.	`data`
Base64 Image Content	Conditional	Base64-encoded content of the source image. Required when Input Data Type is Base64 String.	`/9j/4AAQSkZJRgAB...`
Image URL	Conditional	Publicly reachable HTTPS URL to the source image. Required when Input Data Type is URL.	`https://example.com/photo.jpg`
Output File Name	Required	Filename for the resized image. Include the extension matching the output format.	`resize_image_output.jpg`
Resize Type	Required	Scaling method. Percentage scales relative to the original size, Specific targets exact pixel dimensions. Your choice decides which fields appear next.	`Percentage`
Resize Percentage	Conditional	Scaling percentage relative to the original. Below 100 reduces, above 100 enlarges. Required when Resize Type is Percentage.	`50`
Width	Conditional	Target width in pixels. Required when Resize Type is Specific.	`800`
Height	Conditional	Target height in pixels. Required when Resize Type is Specific.	`600`
Maintain Aspect Ratio	Optional	Toggle that preserves the original proportions so the image is not stretched. Leave enabled unless you need forced dimensions.	`true`
Async	Optional	Toggle that runs the resize in the background instead of holding the workflow execution open. Useful for large images or long batches.	`true`
Binary Data Output Name	Optional	Name of the binary property the output item exposes. Defaults to data.	`data`

Output Fields

A successful run returns one n8n item carrying the resized image and its dimension report.

Field	Type	What it contains
`Binary (data)`	Binary	The resized image, under Binary Data Output Name (default data).
`fileName`	String	Generated filename, matching Output File Name.
`mimeType`	String	MIME type of the output image, for example image/jpeg or image/png.
`fileSize`	Number	Size of the resized image in bytes.
`originalDimensions`	String	Width and height of the source image in pixels, for example 1920x1080.
`newDimensions`	String	Width and height after resizing, for example 960x540. Compare it against your target to confirm aspect ratio behaviour.
`success`	Boolean	True when the resize completed, false on failure. Use it to branch error handling.
`message`	String	Human-readable status message, carrying success confirmation or error detail.

How Do I Set Up Resize Image in n8n?

Add PDF4me to your n8n workflow and choose the Resize Image action.
In Credential to connect with, select your PDF4me credential or click Create New Credential and paste your API key.
Set Input Data Type to Binary Data (default), Base64 String, or URL and supply the matching source image field.
Set Resize Type to Percentage and fill in Resize Percentage, or to Specific and fill in Width and Height.
Leave Maintain Aspect Ratio enabled to avoid stretching, and enable Async for large images or long batches.
Set Output File Name, execute the node, and check newDimensions on the output to confirm the result.

Typical Setups

Workflow ExamplesCommon n8n workflow patterns using Resize Image.

Thumbnails from product uploads

A new product image lands in cloud storage.
Resize Image runs in Specific mode at the thumbnail grid dimensions.
The thumbnail is written back alongside the full-size original.

Shrink oversized user uploads

A webhook receives a photo submitted through a form.
Resize Image runs in Percentage mode to reduce it proportionally.
The smaller file is stored, keeping storage and bandwidth in check.

Batch normalise an image library

A Loop Over Items node iterates an existing folder of mixed-size images.
Resize Image applies one consistent setting to every item, with Async enabled.
The library ends up uniform without anyone opening an editor.

Resize then compress for the web

An editorial image is pulled from a CMS.
Resize Image brings it down to the display width first.
Compress Image then reduces the file size further before publishing.

Practical Tips

Resize before you compress, not after

Reducing dimensions first means the compressor has less data to work on, which usually gives a better result than compressing a full-size image.

Leave Maintain Aspect Ratio on by default

Turning it off only makes sense when a target slot genuinely demands non-proportional dimensions. Otherwise it silently stretches faces and logos.

Use Percentage for mixed-size inputs

When sources vary, a fixed pixel target crops or pads inconsistently. A percentage keeps every image in proportion to where it started.

Read newDimensions rather than assuming

The output reports both original and new dimensions, which is the fastest way to confirm aspect ratio handling did what you expected.

Match the Output File Name extension to the format

Naming a PNG output with a .jpg extension confuses downstream nodes and any application that opens the file by extension.

Enable Async for large batches

Long-running batches are exactly where a synchronous call risks timing out, and Async keeps the execution from being held open.

Cheat Sheet

Field	Value
Action	`Resize Image`
Input Data Type	`Binary Data`
Input Binary Field	`data`
Output File Name	`resize_image_output.jpg`
Resize Type	`Percentage`
Resize Percentage	`50`
Width / Height (Specific mode)	`800 / 600`
Maintain Aspect Ratio	`true`
Async	`true`
Binary Data Output Name	`data`

Common Questions

Should I resize by percentage or by exact pixel dimensions?+

Use Percentage when the source images vary in size and you want them all reduced or enlarged by the same proportion, for example halving every upload. Use Specific when a target slot demands fixed dimensions, such as a thumbnail grid or a platform that requires an exact width and height.

What happens if I turn off Maintain Aspect Ratio?+

With Maintain Aspect Ratio on, the original proportions are preserved so the image is never stretched. Turning it off lets the width and height you supply be applied independently, which will distort the picture if the target aspect ratio differs from the source. Leave it on unless you specifically need to force non-proportional dimensions.

Does enlarging an image with a percentage above 100 improve its quality?+

No. Scaling above 100 percent increases the pixel dimensions but cannot add detail that was never captured, so an enlarged image will look softer than a natively larger original. Enlarge only when a layout demands the dimensions, and prefer starting from the highest-resolution source you have.

When should I enable Async on the Resize Image node?+

Async Processing runs the resize in the background rather than holding the workflow execution open, which helps with large source images or long batch runs where a synchronous call might otherwise time out.

How do I resize many images in one n8n workflow?+

Feed the images in as multiple items, for example from a folder listing or a Loop Over Items node, and place Resize Image after it. The node runs once per item, so a single configured node handles the whole batch with identical settings rather than needing one node per file.

Compress Image

The natural next step, reducing file size further once dimensions are right.

Crop Image

Use this when you need a different aspect ratio rather than a smaller version of the same frame.

Convert Image Format

Change the file format after resizing when the target platform expects something specific.

Get Image Metadata

Read source dimensions first when the resize decision depends on how big the original is.