Introduction

In Salesforce applications, many business requirements involve generating documents that must be shared, printed, or archived in a fixed format. HTML pages are flexible but may not always provide consistent layout when printed or downloaded.

The renderAs="pdf" attribute allows developers to convert a Visualforce page directly into a PDF document. This enables Salesforce to generate structured and professional documents such as invoices, quotations, and reports without relying on external tools.

What is renderAs="pdf"?

renderAs="pdf" is an attribute of the <apex:page> tag that instructs Salesforce to render the Visualforce page output as a PDF file instead of normal HTML.

● Applied at page level
● Forces PDF generation
● Overrides browser-based rendering
● Executes fully on the server

How renderAs="pdf" Works

When a Visualforce page uses renderAs="pdf", Salesforce processes the request as follows:

● User accesses the Visualforce page
● Apex controller logic executes
● Visualforce markup is evaluated
● HTML is converted into PDF
● PDF file is returned to the user

The entire process happens on the Salesforce server.

Basic Syntax

Example

<apex:page renderAs="pdf" controller="InvoiceController">
    <h1>Invoice</h1>
    <p>Invoice Number: {!invoiceNumber}</p>
</apex:page>

● Page is rendered as a PDF
● Content becomes non-editable
● File can be downloaded or printed

Supported Content with renderAs="pdf"

Supported

● Standard Visualforce components
● Text, tables, and images
● Inline CSS styles
● Apex expressions and data

Not Supported

● JavaScript execution
● AJAX and partial page refresh
● Client-side validations
● Dynamic DOM manipulation

Styling Considerations

Styling PDF pages requires a simplified approach.

● Inline CSS works best
● Table-based layouts are recommended
● Fixed widths and heights ensure alignment
● Avoid floats and complex positioning
● External CSS support is limited

Page Layout and Formatting

PDF layout can be controlled using CSS properties.

● Page size can be defined (A4, Letter)
● Orientation can be portrait or landscape
● Margins can be customized
● Headers and footers can be styled

Using Images in PDF

Images can be included with some limitations.

● Use static resources where possible
● Prefer absolute image URLs
● Fix image dimensions
● Avoid large image files

Controller and Data Handling

Apex controllers prepare all required data before rendering.

● All logic runs before PDF generation
● SOQL queries must be optimized
● Governor limits apply
● Large data volumes increase rendering time

Common Use Cases

renderAs="pdf" is commonly used for:

● Invoice and billing documents
● Sales quotations
● Payment receipts
● Certificates
● Audit and compliance reports

Performance Considerations

PDF rendering consumes more resources than normal page rendering.

● Complex layouts slow rendering
● Large tables increase processing time
● Excessive images impact performance
● Multiple simultaneous PDFs affect limits

Security Considerations

When using renderAs="pdf":

● Enforce object-level security
● Apply field-level security
● Validate user permissions
● Avoid exposing sensitive data

Common Mistakes Developers Make

● Using JavaScript in PDF pages
● Expecting AJAX to work
● Using heavy CSS frameworks
● Not testing PDF layout thoroughly

Best Practices

Follow these best practices for stable PDF generation:

● Keep layout simple
● Use tables for structure
● Minimize CSS complexity
● Optimize Apex logic
● Test with realistic data

Real-World Scenario

In real Salesforce implementations:

● Sales teams generate invoice PDFs
● PDFs are emailed to customers
● Documents are archived automatically
● Users download and print files

Conclusion

The renderAs="pdf" attribute is a powerful feature in Visualforce that enables Salesforce to generate professional, fixed-layout PDF documents directly from the platform. By understanding its behavior, limitations, and best practices, developers can create reliable PDF solutions that support critical business workflows.

VF Page Beginner to Advance

renderAs="pdf" in VF Page