The best PDF APIs for developers in 2026

A PDF API can compress, convert, merge, fill, sign or generate documents from your code. These are the options worth evaluating, and how to choose.

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Updated November 8, 2026 by the PDFbat team

The short answer

The best PDF API depends on the job. For a simple REST API that covers every PDF tool plus e signatures, with 250 free calls a month and pay as you go pricing, PDFbat is a good fit. For enterprise SDKs, viewers and deep document processing, look at Nutrient or Apryse. For high fidelity HTML to PDF generation, DocRaptor is purpose built.

Most teams over buy. If your need is merge, split, compress, OCR, redact and send for signature, a hosted REST API is usually cheaper and faster to ship than a licensed SDK.

We build PDFbat, so we list real trade-offs for every option, including ours.

At a glance

Feature	PDFbat	Adobe PDF Services	Nutrient	PDF.co	iLovePDF API
Style	Hosted REST API	Hosted API and SDKs	SDKs and hosted API	Hosted REST API	Hosted REST API
Free allowance	250 calls a month	Free trial or tier, check their current plans	Free trial, check their current plans	Free trial credits	Free tier with limits
Pricing model	$0.01 per call, less at volume	Per transaction	Custom or tiered	Credit plans	Plans by usage
Failed calls billed	No	Check their current plans	Check their current plans	Check their current plans	Check their current plans
Compress, merge, split	Yes	Yes	Yes	Yes	Yes
OCR	Yes	Yes	Yes	Yes	Check their current plans
Edit and fill forms	Yes	Yes	Yes	Yes	Limited
E signature envelopes	Yes	Via Acrobat Sign	Separate products	No	No
Webhooks	Signed, retried	Check their current plans	Check their current plans	Yes	Check their current plans
OpenAPI spec	Yes	Check their current plans	Check their current plans	Yes	Check their current plans
MCP server for AI assistants	Yes	No	No	No	No

Competitor details reflect their public pricing pages in November 2026. Check their site for current terms.

Our picks

PDFbat

Best for one REST API for PDF tools, forms, e signatures and Drive

250 free calls a month, then $0.01 per call

The PDFbat API exposes every tool, the editor, form filling, signature envelopes, templates, bulk send, Drive and signed webhooks at one base URL. Authentication is a single bearer key, requests are multipart forms, and failed calls are not billed. It also offers an MCP server so AI assistants can use the tools.

Pros

Simple multipart requests and one key
E signatures and Drive in the same API
Failed calls are not billed, with an OpenAPI spec and Swagger explorer

Cons

Newer, with a smaller community and fewer client libraries
Hosted only, no on premise SDK
Fewer enterprise certifications to cite than large vendors

Adobe PDF Services API

Best for high quality conversion and extraction on Adobe's engine

Free tier, then per transaction pricing

Adobe PDF Services offers APIs for creating, converting, combining, OCR and extracting PDF content, with SDKs for several languages. Adobe also sells Acrobat Sign separately.

Pros

Adobe's rendering and extraction quality
Official SDKs in several languages
Strong enterprise backing

Cons

Pricing is per transaction and can climb
Separate products for signing
Check their current plans for tiers

Nutrient (formerly PSPDFKit)

Best for embedded viewers, editors and document processing in your app

Contact sales

Nutrient provides SDKs and a hosted API for viewing, annotating, editing and processing PDFs inside web, mobile and server apps. It is aimed at product teams embedding PDF features.

Pros

Rich embeddable viewer and editor SDKs
Web, mobile and server support
Mature, widely used

Cons

Licensing is quote based
Heavier than a simple REST call
Overkill for basic tool jobs

Apryse (formerly PDFTron)

Best for enterprise SDKs with broad format support

Contact sales

Apryse offers SDKs and server tools for PDF rendering, editing, conversion, redaction and document workflows. It serves large organisations and software vendors.

Pros

Very deep feature set
Many platforms and languages
Enterprise support

Cons

Quote based pricing
Complex to evaluate and integrate
Not aimed at small projects

PDF.co

Best for no code and low code automation of PDF tasks

Free trial, credit based plans

PDF.co offers a hosted REST API with tools for splitting, merging, parsing, barcodes and conversions, plus connectors for Zapier and Make. It is popular for automation workflows.

Pros

No code connectors
Handy parsing and barcode tools
Credit based plans

Cons

Credit pricing needs care to estimate
Documentation spread across many endpoints
Check their current plans

iLovePDF API

Best for adding simple PDF tools to an app fast

Free tier, paid usage plans

The iLovePDF API exposes its tool set, including merge, split, compress, convert and watermark, with SDKs for several languages. Developers use it to add familiar tools to their own sites.

Pros

Simple tool oriented design
Client libraries available
Recognisable service

Cons

Not designed for e signatures or forms workflows
Limited editing
Check their current plans

DocRaptor

Best for generating pixel accurate PDFs from HTML

Free test mode, paid by volume

DocRaptor converts HTML and CSS into PDF with strong support for print CSS, headers, footers and accessibility. It focuses on generation rather than editing existing files.

Pros

Excellent HTML to PDF fidelity
Print CSS support
Simple integration

Cons

Generation only, not a full PDF toolkit
No signature workflow
Pricing scales with document volume

How we picked

We compared well known APIs that developers actually ship with. Each was judged on the points below, using public documentation and pricing.

Coverage: tools, editing, forms, OCR and signatures.
Pricing model and what a failed call costs.
Developer experience: docs, OpenAPI spec, SDKs and webhooks.
Hosted or embedded: REST service or an SDK you ship.
Free allowance for prototyping.
Fit for AI assistant workflows, such as an MCP server.

Hosted API or embedded SDK?

A hosted REST API is the fastest route: send a file, get a file back, and pay per call. It suits back office automation, SaaS features such as export and merge, and prototypes. An embedded SDK suits products that need a PDF viewer or editor inside their own interface, with offline use or strict data residency.

PDFbat is a hosted API. See the PDF API page for endpoints and examples.

Using a PDF API with AI assistants

AI assistants can now call tools directly through the Model Context Protocol. PDFbat ships an MCP server, so an assistant can compress, merge, redact or send a document for signature through the same tools your code uses.

If agent workflows matter to you, check whether a vendor offers an MCP server or only a conventional API.

Frequently asked questions

What is the best PDF API?

It depends on the job. PDFbat is a good choice for a hosted REST API covering tools and e signatures. Nutrient and Apryse suit embedded SDKs, and DocRaptor suits HTML to PDF generation.

Is there a free PDF API?

PDFbat includes 250 free calls a month. Others offer free tiers or trials, so check their current plans.

How much does the PDFbat API cost?

After 250 free calls a month it is $0.01 per call, and $0.005 per call above 10,000 a month. Failed calls are not billed.

Can a PDF API send documents for signature?

PDFbat can create envelopes, add recipients and fields, send, remind and download the sealed PDF, with signed webhooks. Most other PDF APIs treat signing as a separate product.

Which PDF API is best for HTML to PDF?

DocRaptor is purpose built for high fidelity HTML to PDF generation. General tool APIs may also convert but check the output quality for your templates.

Do I need an SDK?

Not for a REST API. You can call PDFbat with curl or any HTTP client, and the OpenAPI spec can generate a client.

Keep comparing

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