SnapOtter/apps/docs/tools/pdf/compress-pdf.md

description

description
Shrink PDF file size by compressing embedded images.

Compress PDF

Reduce PDF file size by downsampling embedded images. Choose between a quality slider or a target file size.

API Endpoint

POST /api/v1/tools/pdf/compress-pdf

Accepts multipart form data with a PDF file and a JSON settings field.

Parameters

Parameter	Type	Required	Default	Description
mode	string	No	"quality"	Compression mode: quality or targetSize
quality	integer	No	75	Compression quality, 1-100 (higher = less compression). Used in quality mode
targetSizeKb	number	No	-	Target file size in kilobytes. Used in targetSize mode

Example Request

Compress by quality:

curl -X POST http://localhost:1349/api/v1/tools/pdf/compress-pdf \
  -H "Authorization: Bearer si_your-api-key" \
  -F "file=@document.pdf" \
  -F 'settings={"mode": "quality", "quality": 60}'

Compress to a target size:

curl -X POST http://localhost:1349/api/v1/tools/pdf/compress-pdf \
  -H "Authorization: Bearer si_your-api-key" \
  -F "file=@document.pdf" \
  -F 'settings={"mode": "targetSize", "targetSizeKb": 500}'

Example Response

{
  "jobId": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
  "downloadUrl": "/api/v1/download/a1b2c3d4-e5f6-7890-abcd-ef1234567890/document.pdf",
  "originalSize": 5200000,
  "processedSize": 1800000
}

Notes

• In quality mode, lower values produce smaller files with more image degradation.
• In targetSize mode, a binary search finds the highest DPI that fits the requested size.
• If compression would enlarge the file, the original bytes are returned unchanged.
• Text and vector content are not affected; only embedded raster images are downsampled.