---
title: PDF Compress API - Reduce PDF File Size Programmatically
version: 1.0.0
description: "Compress a PDF file to reduce its file size. Supports four compression levels: low (preserves quality), balanced (optimal ratio), high (significant reduction), and extreme (maximum compression). Accepts a file upload or an existing file ID. Returns a task ID for tracking the compression progress."
openapi: 3.1.1
servers:
  - https://api.apifreaks.com/v1.0
paths: 1
operations: 1
schemas: 3
---

## Table of Contents

- [PDF Compress API - Reduce PDF File Size Programmatically v1.0.0](#pdf-compress-api-reduce-pdf-file-size-programmatically-v100)
  - [Authentication](#authentication)
  - [PDF Operations APIs](#pdf-operations-apis)
    - [compressPdf](#compresspdf)
      - [Parameters](#parameters)
      - [Responses](#responses)
  - [Schemas](#schemas)
    - [PdfTaskResponse](#pdftaskresponse)
    - [PdfFileUploadRequest](#pdffileuploadrequest)
    - [ErrorResponse](#errorresponse)



# PDF Compress API - Reduce PDF File Size Programmatically v1.0.0

Compress a PDF file to reduce its file size. Supports four compression levels: low (preserves quality), balanced (optimal ratio), high (significant reduction), and extreme (maximum compression). Accepts a file upload or an existing file ID. Returns a task ID for tracking the compression progress.

Base URLs:

* [https://api.apifreaks.com/v1.0](https://api.apifreaks.com/v1.0)

## Authentication

* API Key (ApiKeyAuthHeader)
    - Parameter Name: **X-apiKey**, in: header. Pass your API key via the X-apiKey request header.

* API Key (ApiKeyAuthQuery)
    - Parameter Name: **apiKey**, in: query. Pass your API key via the apiKey query parameter.

## PDF Operations APIs

### compressPdf

`POST /pdf/compress`

*Compress a PDF file*

This API compresses a given PDF file to reduce its file serize.

> Body parameter

```yaml
file: string

```

#### Parameters

|Name|In|Type|Required|Description|
|---|---|---|---|---|
|format|query|string|false|Specifies the desired format for the API response. Choose 'json' for a JSON object or 'xml' for an XML structure.|
|file_id|query|string|false|The unique ID of a PDF file already uploaded to the API Freaks server. Use this as an alternative to uploading a new file.|
|output|query|string|false|Name of the output PDF.|
|compression_level|query|string|true|Controls how aggressively the PDF is compressed. Lower levels preserve more quality, while higher levels reduce file size more.|
|destroy|query|boolean|false|If set to true, the input file(s) will be deleted from the server immediately after the output is generated.|
|webhook_url|query|string|false|The URL to which the webhook notification will be sent after the task is completed.|
|webhook_failure_notification|query|boolean|false|If true, a notification will also be sent by email in case the webhook request fails all the retries.  The email notification will be sent to the requesting user or their organization’s admin if part of one.|
|X-Webhook-Authorization|header|string|false|Optional custom header for webhook requests. Format: `Key:Value` (e.g., `Authorization:Bearer token123`). This will be sent as an HTTP header in the webhook call.|
|body|body|[PdfFileUploadRequest](#pdffileuploadrequest)|false|Multipart form-data body carrying the PDF file to compress. Alternatively, reference an already-uploaded file via the file_id query parameter instead of uploading here.|

##### Enumerated Values

|Parameter|Value|
|---|---|
|format|json|
|format|xml|
|compression_level|low|
|compression_level|balanced|
|compression_level|high|
|compression_level|extreme|

> Example responses

> Compression task created successfully

```json
{
  "taskId": "ce4b1a38-6cfc-4373-9bd7-ff186fbd8e7e",
  "inputIds": [
    "f2ba4b50-6f8a-43ae-b42d-96937f50cd89"
  ]
}
```

> Bad Request — Missing/invalid parameters or file ID

```json
{
  "error": "Invalid Param Exception",
  "message": "please pass correct parameters",
  "path": "/v1.0/pdf/compress",
  "status": 400,
  "timestamp": "2026-07-27T10:50:09.307Z"
}
```

```json
{
  "timestamp": "2026-07-27T10:50:09.886Z",
  "path": "/v1.0/pdf/compress",
  "status": 400,
  "error": "Missing File or ID",
  "message": "Please provide either a file or a file ID."
}
```

```json
{
  "error": "Invalid File ID Provided",
  "message": "Please provide a valid file ID",
  "path": "/v1.0/pdf/compress",
  "status": 400,
  "timestamp": "2026-07-27T10:50:25.910Z"
}
```

> Unsupported Media Type — File type not supported

```json
{
  "timestamp": "2026-07-27T10:50:18.409Z",
  "path": "/v1.0/pdf/compress",
  "status": 415,
  "error": "Unsupported File Type",
  "message": "The provided file type is not supported. Refer to the documentation for valid file types."
}
```

#### Responses

|Status|Meaning|Description|Schema|
|---|---|---|---|
|200|[OK](https://tools.ietf.org/html/rfc7231#section-6.3.1)|Compression task created successfully|[PdfTaskResponse](#pdftaskresponse)|
|400|[Bad Request](https://tools.ietf.org/html/rfc7231#section-6.5.1)|Bad Request — Missing/invalid parameters or file ID|[ErrorResponse](#errorresponse)|
|415|[Unsupported Media Type](https://tools.ietf.org/html/rfc7231#section-6.5.13)|Unsupported Media Type — File type not supported|[ErrorResponse](#errorresponse)|

#### Response Headers

|Status|Header|Type|Format|Description|
|---|---|---|---|---|
|200|X-AF-Credits-Cost|integer||Specifies the number of credits consumed by the current request.|
|400|X-AF-Credits-Cost|integer||Specifies the number of credits consumed by the current request.|
|415|X-AF-Credits-Cost|integer||Specifies the number of credits consumed by the current request.|

To perform this operation, you must be authenticated by means of one of the following methods:
ApiKeyAuthHeader, ApiKeyAuthQuery

## Schemas

### PdfTaskResponse

Response containing the task ID and input file IDs for a PDF processing task.

#### Properties

|Name|Type|Required|Restrictions|Description|
|---|---|---|---|---|
|taskId|string|true|none|Task ID of the requested task, used to check the task status.|
|inputIds|[string]|false|none|File IDs for the input files provided for the task. Not returned when destroy parameter is true.|

### PdfFileUploadRequest

Multipart form-data request body containing the PDF file to process.

#### Properties

|Name|Type|Required|Restrictions|Description|
|---|---|---|---|---|
|file|string(binary)|false|none|Raw PDF file bytes sent as a multipart/form-data field named 'file'. Omit this field entirely and pass file_id in the query string instead to use an already-uploaded file.|

### ErrorResponse

Standard error envelope returned by the API on failed requests.

#### Properties

|Name|Type|Required|Restrictions|Description|
|---|---|---|---|---|
|error|string|false|none|Short error category or exception type.|
|message|string|true|none|Human-readable error message describing the failure.|
|path|string|false|none|API endpoint path that produced the error.|
|status|integer|false|none|HTTP status code returned with the error.|
|timestamp|string(date-time)|false|none|Timestamp when the error occurred (ISO 8601).|