PDF Write String API — Add Text to Existing PDFs

Add text to existing PDF documents with customizable styling and positioning using PdfBroker.io. Useful for templates like diplomas, certificates, or any document where user-specific text needs to be added.

Endpoint

POST https://api.pdfbroker.io/api/pdf/pdfwritestring

Request Parameters

Parameter	Type	Description
`pdfFileBase64String`	string	Base64-encoded PDF file content
`fontFileBase64String`	string	Optional Base64-encoded TrueType font file
`options`	object	Configuration for text placement and styling

Text Options

Option	Type	Default	Description
`text`	string	Required	Content to write
`textColor`	object	Black (0,0,0)	RGB values as object with `r`, `g`, `b` properties
`font`	object	—	Name, size, and style (0=Normal, 1=Bold, 2=Italic, 3=Bold+Italic)
`pageNumber`	integer	1	Target page number
`xPosition`	float	—	Horizontal offset from xOrigin
`yPosition`	float	—	Vertical offset from yOrigin
`xOrigin`	integer	0	Reference point: 0=Left, 1=Center, 2=Right
`yOrigin`	integer	0	Reference point: 0=Top, 1=Center, 2=Bottom

Example Request

{
    "pdfFileBase64String": "JVBERi0xLjcNCiW1tbW1...",
    "options": {
        "text": "John Doe",
        "textColor": { "r": 0, "g": 0, "b": 0 },
        "font": { "name": "Arial", "size": 24, "style": 1 },
        "pageNumber": 1,
        "xPosition": 0,
        "yPosition": 0,
        "xOrigin": 1,
        "yOrigin": 1
    }
}

Note

See the Swagger documentation for the complete API specification. A live demo is also available.