Best HTML to PDF APIs compared

The best HTML to PDF APIs in 2026 are Transformy (headless-Chrome rendering with storage delivery and webhooks), DocRaptor (Prince XML for print-grade fidelity), PDFShift (a clean Chromium API), and api2pdf (cheapest per PDF at scale). The right pick depends on three things: which rendering engine your documents need, what the API really costs at your monthly volume, and whether compliance is in play.

Here's the truth about this corner of the internet: every ranking roundup for this query was written by a vendor, about themselves. We're a vendor too, and we say so: Transformy is on this list, scored on the same axes as everyone else, and we name the use cases where a competitor is the better buy. You'll get the 8-item shortlist, a comparison table, per-vendor reviews, an engine explainer, and the cost math at 10,000 PDFs a month.

Key TakeawaysVerified prices at 10,000 PDFs a month run from ~$25 (api2pdf, usage-based) to $399 (DocRaptor Bronze), a roughly 16× spread driven by engine and metering model, not quality alone.Engine determines fidelity: Chromium APIs (Transformy, PDFShift, PDFEndpoint) render like the browser; Prince XML (DocRaptor) wins print-grade paged media; legacy engines (wkhtmltopdf offerings, SelectPDF's default WebKit) fail on modern CSS.Metering models are the hidden trap. Per-document pricing is predictable; per-credit-by-output-size (1 credit per 5MB at PDFShift, per 0.5MB at PDFCrowd) can multiply costs on image-heavy documents.wkhtmltopdf-based API tiers are a liability: the engine was archived in 2023 and carries an unpatched 9.8-severity SSRF CVE. Migrate forward, not sideways.Best free tiers to prototype with: Transformy (100 docs/month + unlimited watermarked test renders), PDFShift (50 credits/month), DocRaptor (unlimited free test documents).

What is an HTML to PDF API?

An HTML to PDF API is a web service that converts HTML, either raw markup or a live URL, into a PDF document via a single HTTP request. It renders the page with an engine like headless Chrome or Prince XML and returns the finished PDF, so you don't run or scale a browser yourself.

Vendors also market this as an HTML to PDF converter API or a PDF generation API; it's the same product. In practice you POST your HTML with an API key, and the response is PDF bytes, a hosted URL, or a file dropped into your cloud storage. The API owns the browser fleet, the font rendering, the scaling, and the patching. You own one HTTP call.

How we compared these HTML to PDF APIs

We scored the most popular HTML to PDF APIs on eight criteria, applied identically to every vendor:

• Rendering engine: Chromium, Prince XML, or something older; this decides what CSS survives.
• Fidelity: flexbox, grid, webfonts, JavaScript execution, print CSS.
• Verified cost at 10,000 docs/month: checked July 26, 2026, assuming ~1MB average output and ~2-second renders. Where a vendor hides pricing, we say so instead of estimating.
• Free tier: what you can prototype without a credit card.
• Metering model: per document, per size-based credit, or usage-based; this is where surprise bills live.
• Limits: timeouts, file-size ceilings, concurrency.
• Developer experience: docs quality, error handling (JSON errors versus an error page rendered into your PDF), request tracing. Our own HTML to PDF API docs show the bar we hold ourselves to.
• Compliance: SOC 2, HIPAA, data residency, where the vendor documents it.

The 8 best HTML to PDF APIs at a glance

1. Transformy, headless-Chrome fidelity plus document plumbing (storage delivery, webhooks, idempotency).
2. DocRaptor, Prince XML engine; the print-grade choice for regulated documents.
3. PDFShift, clean Chromium API with a generous free tier.
4. api2pdf, usage-based pricing; cheapest at almost any volume.
5. PDFEndpoint, budget Chromium rendering with simple per-conversion pricing.
6. SelectPDF, metered plans up to a true unlimited tier; watch the default engine.
7. CraftMyPDF, template-first PDF platform with HTML support.
8. PDFCrowd, long-running converter API; per-0.5MB credit metering.

1. Transformy

Transformy's HTML to PDF API renders every document with real headless Chromium: one authenticated POST with raw HTML or a URL, one pixel-accurate PDF back. If it renders in Chrome, it renders in the PDF, including JavaScript-heavy SPAs, webfonts, grid, and print CSS.

What separates it from the mid-market Chromium pack is the plumbing around the render. Finished PDFs can return as bytes, a hosted URL, base64, or land directly in your own S3, GCS, Azure, or R2 bucket. Async jobs fire signed webhooks. Idempotency keys prevent duplicate renders on retries. Errors come back as JSON with an X-Request-Id, never as an error page rendered into a PDF. Tagged (accessible) PDFs and heading-based bookmarks are parameters, not enterprise add-ons.

Pricing reality: free tier is 100 documents a month with no credit card; test keys render real, watermarked PDFs free and unlimited. Pro is $99/month for 10,000 documents, then $0.01 per extra document. Per-document metering, so image-heavy files don't inflate the bill.

Watch out for: single engine by design. If you need Prince XML's paged-media features specifically, or an on-prem deployment, look at DocRaptor or self-hosting instead. We'd rather tell you that here than in your rendering backlog.

2. DocRaptor

DocRaptor is the only major API built on the commercial Prince XML engine, and it shows in print-grade output: leaders, footnotes, cross-references, running headers, and CSS Paged Media support that browser engines still don't match. For financial statements, contracts, and regulated documents with strict layout rules, it's the reference pick.

The tradeoff is the other direction: Prince is not a browser. JavaScript-rendered content is its weak spot, so SPA dashboards and client-rendered charts need pre-rendering before DocRaptor sees them.

Pricing reality (verified on their signup page): free plan covers 5 production documents a month with unlimited free test documents. Paid tiers climb from Basic at $15 (125 docs) through Max at $149 (5,000) to Bronze at $399 (15,000). At 10,000 documents you're on Bronze: $399/month, the most expensive verified price in this roundup by a wide margin.

Watch out for: the tier jumps are steep (5,000 docs for $149, then nothing until 15,000 for $399). DocRaptor markets SLA and compliance credentials; they weren't listed on the signup page we verified, so confirm SOC 2/HIPAA specifics with their security documentation before committing regulated workloads.

3. PDFShift

PDFShift is a focused Chromium API with one of the friendlier free tiers in the market: 50 credits a month, no credit card. The feature set covers the essentials well: CSS/JS injection, headers and footers, encryption, watermarking, S3 delivery, and async responses.

Pricing reality: Starter at $9, Boost at $24 (2,500 credits), Growth at $39 (5,000 credits), per third-party listings; the vendor's own pricing page loads tiers dynamically, and tiers above Growth aren't publicly listed. At 10,000 documents a month you're beyond the published plans, so budget for overage ($0.025/conversion on Growth) or contact them.

Watch out for: the metering rule. One credit covers 5MB of generated output, so a 14MB document costs 3 credits. For invoice-sized PDFs that's irrelevant; for image-heavy reports it quietly multiplies the bill.

4. api2pdf

api2pdf takes the opposite approach to everyone else: pure usage-based pricing at $1/month base plus $0.001 per MB of bandwidth and about $0.0002 per second of compute (their pricing page publishes the formula). Run the math on 10,000 one-megabyte PDFs with 2-second renders and you land around $25/month, the cheapest verified number in this comparison.

Pricing reality: that ~$25 is assumption-dependent. Heavier documents and slower renders move it, but even at double the assumptions it undercuts every flat plan here.

Watch out for: api2pdf still offers wkhtmltopdf and LibreOffice endpoints alongside Chrome. The wkhtmltopdf option is exactly what the engine section below warns about: an archived engine with unpatched CVEs. Use their Chrome endpoint and treat the legacy ones as off-limits for anything touching untrusted HTML. Reliability tuning (retries, timeout handling) is also more your job than with the managed-plan vendors.

5. PDFEndpoint

PDFEndpoint is the budget pick among the Chromium APIs with published pricing: free for 100 conversions a month, $9 for 500, $24 for 5,000, and $39 for 10,000, with per-conversion overage beyond your plan. A conversion is simply a successful PDF, no size-based credit math.

Pricing reality: $39/month at our 10,000-document benchmark, roughly 40% of Transformy's price and a tenth of DocRaptor's.

Watch out for: you're buying rendering, not plumbing. Delivery options, webhook workflows, and compliance documentation are thinner than the bigger vendors; the site itself is light on operational detail. Prototype against your hardest real document before committing.

6. SelectPDF

SelectPDF sells metered monthly plans from $19 (2,000 conversions) up to $449, topped by a Dedicated tier with genuinely unlimited conversions, the only true unlimited offer in this roundup. A nice metering quirk: one conversion credit covers up to 50 PDF pages, so a 1-page and a 49-page document cost the same.

Pricing reality: at 10,000 documents a month you'd sit on their Advanced tier (20,000 conversions); the full tier ladder runs $19–$449. High-volume, long-document workloads are where their model shines.

Watch out for: the default rendering engine is legacy WebKit. Their own docs recommend the Chromium engine "for new integrations", but you must opt in via the engine parameter. Leave the default and modern CSS (grid, current flexbox behavior) will quietly degrade, a fidelity gotcha that has nothing to do with price.

7. CraftMyPDF

CraftMyPDF is a different shape of product: a drag-and-drop template editor first, with an API to fill templates with data, and HTML-to-PDF conversion as a supporting feature. If your documents are designed layouts (certificates, branded invoices) maintained by non-developers, that model is genuinely useful.

Pricing reality (verified on their pricing page): free plan covers 50 PDFs and 3 templates; Lite $29 (1,200 PDFs), Plus $49 (3,000), Professional $99 (12,000). At 10,000 a month you're on Professional at $99, price-matched with Transformy.

Watch out for: if what you have is existing HTML you want converted faithfully, a template-first platform adds a layer you don't need, and template counts become a second quota to manage. Compare it against raw HTML-to-PDF APIs only if you actually want the editor.

8. PDFCrowd

PDFCrowd is one of the longest-running converter APIs, with SDKs across most languages and a Chromium-based rendering path. The trial gives you 100 credits for a month.

Pricing reality: paid pricing sits behind an interactive volume selector on their site rather than a public table, so we can't verify a 10,000-document price, and we won't guess. Their metering is the strictest in this roundup: one credit per 0.5MB of output, so a 1MB PDF costs 2 credits. Model your real document sizes before trusting any per-credit comparison.

Watch out for: that 0.5MB credit rule is the sharpest version of the metering trap in this article. A workload that averages 2MB per document effectively pays 4× the headline credit count.

Also on the radar: ConvertAPI (a 500-format conversion suite where HTML-to-PDF is one endpoint; its site blocks automated pricing checks, so verify costs on their calculator directly) and ScreenshotEngine (a newer entrant whose PDF product is still thin on operational detail).

Chromium vs Prince XML vs legacy engines: which do you need?

Every API above is ultimately selling you a rendering engine with an HTTP wrapper. There are only three families that matter.

Chromium (Transformy, PDFShift, PDFEndpoint, api2pdf's Chrome endpoint, PDFCrowd, CraftMyPDF) renders your document exactly like the browser your users run: full modern CSS, JavaScript execution, webfonts. If your source is a web page, a React dashboard, or templates your front-end team styles, Chromium is the correct default. Integrating from a backend? Our Node.js HTML-to-PDF guide walks the same decision from the code side.

Prince XML (DocRaptor) implements CSS Paged Media beyond what browsers do: footnotes, leaders, page-region controls, cross-references. For book-like and compliance-grade documents it's unmatched. It is not a browser, so JavaScript-dependent content is out of scope.

Legacy engines are the trap. wkhtmltopdf was archived in January 2023 (organization-wide by July 2024) and ships a ~2016 WebKit with unpatched vulnerabilities, including CVE-2022-35583, a 9.8-severity SSRF. Any API still selling a wkhtmltopdf tier is selling you that frozen engine, and SelectPDF's default WebKit sits in the same family even without the CVE headline. If you're migrating off wkhtmltopdf today, our wkhtmltopdf alternatives comparison covers the full landscape; the short version is: migrate forward to the engine the modern web runs on, not sideways to another frozen renderer.

Here's how the engine choice goes wrong in practice. Picture a two-person fintech team, call the lead Dana, shipping account statements through a cheap API's legacy endpoint because it was $15 a month cheaper than the Chrome tier. The statements looked fine until the design team introduced a CSS grid layout for transaction tables. The legacy WebKit silently linearized the grid into a single column, and statements went out misformatted for three weeks before a customer complained. The fix took an afternoon: switching to the Chrome endpoint. The engine was the product all along; the $15 was never the real price.

HTML to PDF API pricing: what it really costs at scale

Vendors meter four different ways, and the model matters more than the sticker price:

• Per document (Transformy, DocRaptor, PDFEndpoint, CraftMyPDF): a PDF is a PDF. Predictable, immune to file size.
• Per size-based credit (PDFShift: 1 credit/5MB; PDFCrowd: 1 credit/0.5MB): cheap for small invoices, multiplies on image-heavy output.
• Usage-based (api2pdf: bandwidth + compute): cheapest on paper, variable in practice; you're carrying the estimation risk.
• Per conversion with page allowance (SelectPDF: up to 50 pages per credit): favors long documents.

At our benchmark of 10,000 ~1MB documents a month, the verified spread runs ~$25 (api2pdf) → $39 (PDFEndpoint) → $99 (Transformy, CraftMyPDF) → $399 (DocRaptor), with PDFShift, SelectPDF, and PDFCrowd requiring vendor contact or tier-ladder reading at that volume. That's a 16× gap between verified endpoints, and the expensive end isn't "worse value": DocRaptor's premium buys Prince XML fidelity nothing else here can render. Pick the engine your documents need first, then compare prices inside that family.

Prototyping without spending anything: Transformy's test keys render real, watermarked PDFs with no quota and no card, DocRaptor's test documents are unlimited and free, and PDFShift's 50 monthly credits reset forever. Run your ugliest production document through all three before you believe any comparison table, including this one.

FAQ

What is the best HTML to PDF API?

Transformy for browser-accurate rendering with delivery plumbing (webhooks, cloud storage, idempotency), DocRaptor if you need Prince XML's print-grade paged media, and api2pdf if lowest cost at scale is the deciding factor. Match the engine to your documents first; every other criterion is secondary.

Which HTML to PDF APIs have a free tier?

Transformy gives 100 documents a month plus unlimited watermarked test renders, PDFShift gives 50 credits a month, PDFEndpoint gives 100 conversions, DocRaptor gives 5 production documents with unlimited test docs, and SelectPDF runs a 200-conversion trial. All work without a credit card. If you want a free HTML to PDF API for ongoing low volume rather than a trial, the recurring allowances (Transformy, PDFShift, PDFEndpoint) are the ones that don't expire.

Are wkhtmltopdf-based APIs still safe to use?

Not for untrusted or user-supplied HTML. The wkhtmltopdf project was archived in 2023 and carries an unpatched 9.8-severity SSRF vulnerability (CVE-2022-35583) plus a frozen ~2016 WebKit that mangles modern CSS. Prefer the vendor's Chromium endpoint, or migrate to a Chrome-based API.

What's the cheapest way to convert HTML to PDF at scale?

Among managed APIs, api2pdf's usage-based model lands around $25 for 10,000 typical documents a month, and PDFEndpoint's flat $39 for 10,000 is the cheapest published per-document plan. Self-hosting Puppeteer is cheaper on paper but moves browser operations, scaling, and patching onto your team; our Puppeteer alternatives and Gotenberg alternatives pages cover that build-vs-buy line honestly.

Do I need SOC 2 or HIPAA for PDF generation?

Only if the documents contain regulated data (health records, financial PII) and your own compliance program requires vendors to attest. If so, get the vendor's current SOC 2 report or BAA in writing; marketing-page badges aren't attestation. For everything else, standard API security practices (scoped keys, TLS, short-lived hosted URLs) are the practical bar.

Conclusion

Choosing among the best HTML to PDF APIs comes down to three questions, in order:

• Which engine do your documents need? Web-styled content → Chromium (Transformy, PDFShift, PDFEndpoint). Print-grade paged media → Prince XML (DocRaptor). Legacy engines → migrate away, don't buy in.
• What's your metering exposure? Big or image-heavy documents punish size-based credits; predictable volumes fit per-document plans.
• What does the render sit inside? If you need storage delivery, webhooks, retries, and accessible PDFs, plumbing depth separates otherwise similar Chromium APIs.

At 10,000 documents a month the verified spread is ~$25 to $399, and every serious option here has a free way to test. Use it: render your hardest real document, not a hello-world page, through your top two picks before deciding.

If browser-accurate rendering with the plumbing already built is what you're after, render your first PDF on Transformy's free tier: 100 documents a month, unlimited watermarked test renders, no credit card. Your ugliest invoice is the real benchmark; send it.