PDF converter API for Office, HTML, image, and document workflows

Convert Word, Excel, PowerPoint, HTML, Markdown, images, and other supported files to PDF through a REST API. Send a source file from a backend and receive PDF output in one request — without Microsoft Office, desktop software, or self-managed conversion infrastructure. Use the direct conversion endpoint for straightforward file-to-PDF requests, or use /build for advanced conversion controls or additional document-processing steps.

CONVERT FROM
CONVERT TO

Convert Word, Excel, and PowerPoint files to PDF with our Office-to-PDF API.

Convert text files to PDF documents with our text-to-PDF conversion API.

Use our image-to-PDF conversion API to convert JPG, PNG, and TIFF files to PDF.

Convert HTML files to PDF documents with our HTML-to-PDF conversion API.

Convert Markdown to styled PDF documents with built-in templates and custom CSS.

What can you convert to PDF?

Convert more than 20 supported file formats across Microsoft Office, images, HTML, Markdown, text, and OpenDocument files. Use the selector above to see the exact conversion request for a given source format.

Source group Supported inputs Common use cases
Word
DOC, DOCX
Contracts, reports, proposals, letters, and business documents
Excel
XLS, XLSX
Financial reports, exports, schedules, tables, and operational records
PowerPoint
PPT, PPTX
Presentation sharing, review, printing, and archiving
Images
JPG, PNG, BMP, TIFF, HEIC, WebP, SVG, GIF, TGA, EPS
Scans, receipts, photos, forms, and multipage document packets
Web and markup
HTML, MD
Invoices, application exports, reports, documentation, and generated content
Text and OpenDocument
TXT, RTF, ODT
Text documents, legacy files, and open document workflows

Convert Word to PDF via API

Convert DOC and DOCX documents into stable, layout-consistent PDF output for contracts, reports, proposals, and correspondence, without running Microsoft Word on application servers. For DOCX files, the advanced /build endpoint also controls how tracked changes and comments appear in the resulting PDF. Explore the Word-to-PDF API for complete examples.

Convert Excel to PDF via API

Convert XLS and XLSX spreadsheets into PDFs for reports, financial statements, operational records, schedules, and exports. When the source workbook has a defined print area, the advanced /build endpoint can limit PDF output to that area. Explore the Excel-to-PDF API for spreadsheet-specific guidance.

Convert PowerPoint to PDF via API

Convert PPT and PPTX presentations into fixed-layout PDFs for download, sharing, review, printing, and archiving, without requiring recipients to open the original file. Explore the PowerPoint-to-PDF API for presentation-specific examples.

Convert HTML to PDF via API

Turn HTML and CSS into PDFs for invoices, reports, statements, certificates, and dynamically generated documents, with control over assets, fonts, page sizes, margins, headers, and footers. Explore the HTML-to-PDF API or the PDF generator API for generating new PDFs from templates and application data.

Convert images to PDF via API

Convert JPG, PNG, BMP, TIFF, HEIC, WebP, SVG, GIF, TGA, and EPS files into PDF documents for scans, receipts, photos, forms, and uploaded document pages. A /build request can combine several images into one multipage PDF in a specified order. Explore the image-to-PDF API for image-specific guidance.

Convert Markdown, text, and OpenDocument files to PDF

Turn Markdown, TXT, RTF, and ODT files into PDFs for documentation, reports, release notes, and text-based publishing workflows. Markdown conversion supports styled output, built-in templates, custom CSS, and GitHub Flavored Markdown. Explore the Markdown-to-PDF API for styling and template options.

Convert webpages and URLs to PDF

Capture a hosted webpage as a PDF without first downloading and packaging its HTML as a local source file, for reports, records, receipts, and other pages worth preserving as a document. Explore the URL-to-PDF API for configuration details.

Convert multiple source files into one PDF

A conversion workflow doesn’t need to begin with only one file type. The /build endpoint’s parts array assembles several supported inputs in order — for example, adding an image cover to a Word report, combining several scans into one multipage PDF, or mixing existing PDFs with newly converted inputs.


Convert files — then continue processing the PDF

File conversion is often only the first step. Nutrient DWS Processor API can combine conversion with other document operations instead of passing the output between separate services.

Make converted documents searchable

Apply OCR to scans and image-based documents so users and downstream systems can search the resulting PDF.

Assemble complete document packets

Convert several files, merge them with existing PDFs, and control the final page order.

Add document controls

Apply text or image watermarks, flatten annotations and forms, or redact sensitive content before delivering the final document.

Prepare PDFs for distribution

Optimize and compress the resulting PDF, or linearize it for faster web viewing.

Create archive-ready output

Produce PDF/A output when the workflow requires a document format intended for long-term preservation via the PDF-to-PDF/A API.


Two ways to convert files to PDF

Direct conversion endpoint

Use /processor/convert_to_pdf for a straightforward conversion from one supported source file into PDF — the simplest option for standard Word, Excel, PowerPoint, image, and similar file-to-PDF requests.

Advanced Build API

Use /build for advanced Office conversion parameters, several source files in one resulting PDF, conversion followed by OCR or watermarking, PDF optimization or PDF/A output, or a larger document-processing workflow in one request.


Built for backend document workflows

No Microsoft Office dependency

Convert Word, Excel, and PowerPoint files in Nutrient’s hosted environment without installing or automating Microsoft Office on application servers.

REST API and client libraries

Call the API from any backend that can make an HTTP request, with ready-to-run examples for Shell, Java, C#, JavaScript, Python, PHP, and HTTP, plus official TypeScript/JavaScript and Python clients.

Secure document processing

Nutrient’s infrastructure is SOC 2 Type 2 audited and GDPR-compliant. API communication uses HTTPS. Data-retention behavior depends on the applicable plan and configuration.

Scalable processing

Use single requests for user-triggered conversions, or send concurrent requests for higher-volume processing.

One PDF conversion hub

Use this page when the workflow is broadly about converting documents into PDF before settling on the exact input format.

Built for API-first conversion

Use REST, Postman, JavaScript, Python, Java, C#, PHP, or HTTP to validate conversion workflows without running document infrastructure.

Commercial-ready evaluation path

Connect broad conversion questions to exact task pages, getting started, pricing, and trust surfaces so teams can move from exploration to execution quickly.

Choose the right conversion page

Use this page when the required output is PDF and multiple source formats are still in play. Use a dedicated page once the exact source format is set and the workflow needs focused examples or configuration guidance.

Requirement Best page
Compare all supported file-to-PDF inputs
PDF converter API — this page
Convert DOC or DOCX files
Convert XLS or XLSX files
Convert PPT or PPTX files
Compare Word, Excel, and PowerPoint conversion
Convert HTML and CSS
Generate documents from templates or data
Convert image files
Convert Markdown content
Convert a hosted webpage
Compare conversions with other output formats

PDF converter API FAQs

What is a PDF converter API?

A PDF converter API lets an application send a supported source file and receive PDF output through an HTTP request. It automates conversion inside uploads, backend services, reporting systems, document-management applications, archives, scheduled jobs, and other business workflows.

What file formats can be converted to PDF?

Nutrient supports more than 20 source formats across Microsoft Office, images, HTML, Markdown, text, and OpenDocument files. Supported inputs on this page include DOC, DOCX, XLS, XLSX, PPT, PPTX, RTF, ODT, TXT, JPG, PNG, BMP, TIFF, HEIC, WebP, SVG, GIF, TGA, EPS, HTML, and Markdown. A dedicated URL-to-PDF API is also available for hosted webpages.

Which converter matches a specific input format?

The format selector at the top of this page maps each source format to its dedicated task page. The API tools overview lists every available conversion endpoint.

How is a Word document converted to PDF using an API?

Send a DOC or DOCX file to the direct /processor/convert_to_pdf endpoint with an API key and the correct content type; the response contains the resulting PDF. Use /build instead for advanced Word options, such as controlling how the output PDF renders tracked changes and comments. See the Word-to-PDF API.

Is the PDF converter API free?

Nutrient offers a free Processor API tier with 50 credits per month for evaluation. Free-plan output is watermarked, and commercial-use restrictions apply. Enable pay-as-you-go or choose a paid plan for watermark-free output. Review the Processor API pricing page before using the free tier in a production or commercial workflow.

Can multiple files be batch converted to PDF?

Yes, through two different workflows. To produce a separate PDF for every source file, send multiple conversion requests concurrently. To combine several files into one PDF, include the inputs as ordered items in the /build request’s parts array.

What is the difference between the PDF converter API and the file converter API?

The PDF converter API is for workflows where PDF is the required output — it supports Office, image, HTML, Markdown, text, and other source formats. The broader file converter API covers conversion workflows that produce other supported output formats.

What is the difference between the PDF converter API and the PDF generator API?

Use the PDF converter API when a source file already exists — a Word document, spreadsheet, presentation, image, or Markdown file. Use the PDF generator API when creating new documents from HTML, CSS, templates, application data, and fonts.

Is the API GDPR and SOC 2 compliant?

Nutrient’s infrastructure is SOC 2 Type 2 audited, and the Processor API is GDPR-compliant. API communication uses HTTPS. Data retention and document handling can depend on the plan and configuration, so review the current security and privacy documentation as part of a compliance assessment.

Which programming languages can be used?

The REST API works with any programming language or backend capable of making HTTP requests. Nutrient provides examples for Shell, Java, C#, JavaScript, Python, PHP, and raw HTTP. Official client libraries are available for TypeScript/JavaScript and Python.

What is the maximum file size that can be converted?

Test API keys are limited to requests of up to 5 MB and resulting files of up to 5 MB. Limits for live production workflows can differ — check the current API reference or contact Nutrient Support for large-file processing needs.

Convert the first file to PDF

Choose an input format, generate an API request, and add file-to-PDF conversion to an application with Nutrient DWS Processor API. Start with 50 free monthly credits and watermarked output. Enable pay-as-you-go or choose a paid plan for watermark-free output.