ReflowPDF Engine License

Version of 11 November 2026. The current version is at https://api.reflowpdf.com/docs/engine-license/; a copy of the Engine comes with the version it was released under.

1. Who and what#

These terms are a contract between INSEAW LLC, a South Carolina limited liability company, 301 Corday Lane, Greer, SC 29650, United States ("we"), which makes ReflowPDF, and the licensee named in your license or, without a license, whoever uses the Engine ("you"). By installing or using the Engine, or by buying a license, you accept them; if you accept for an organization, you confirm that you may bind it. Buying a license through a ReflowPDF account is also subject to our Terms of Service (https://reflowpdf.com/terms); where they differ, these terms govern the Engine.

The "Engine" is the ReflowPDF engine in every form we distribute it — the program reflowpdf (its archives and container images) and the WebAssembly package @reflowpdf/engine (for web pages, Node.js, Deno, Bun and serverless platforms) — with its documentation and updates. "Print" means making a PDF or page images with the Engine. The third-party works named in the Engine's notices (THIRD-PARTY.md, THIRD-PARTY-NOTICES.md, the license files of the fonts and hyphenation patterns), and the fonts we serve from our catalogue (mostly under the SIL Open Font License 1.1 or the Apache License 2.0), keep their own licenses. The Engine is licensed, not sold.

2. Without a license#

You may install and use the Engine at no charge, for any lawful purpose, under these terms. Without a license every page it prints carries a small ReflowPDF mark: the development mark in a web page served from localhost, *.localhost, 127.0.0.1 or [::1], and the trial mark everywhere else, including the program reflowpdf on any machine. You may keep and share what you print this way, with the mark as it is.

3. Licenses and installations#

A license is bought as a subscription at https://app.reflowpdf.com (account menu, Engine licenses). With an active license, the Engine prints without the mark on the installations the license covers:

An installation is:

• a website: a registrable domain (by the Public Suffix List) with its subdomains, named in your license, whose pages run the WebAssembly package;
• a computer (server, workstation or laptop), virtual machine or container that runs the Engine. Containers are counted instead of the machine that hosts them, and however many programs, processes or applications run the Engine on one of these, it is one installation;
• a serverless function or edge worker (AWS Lambda, Google Cloud Run, Cloudflare Workers and the like): each deployed function is one installation, however many instances of it run.

Where containers start and stop automatically, count the most that run at the same time, not counting overlaps shorter than one hour while a new version replaces an old one. Several licenses add up; more installations than that, or other terms, are agreed with us in writing. Taxes are added where the law requires.

An environment that serves no end users (development, testing, continuous integration) is not an installation. The WebAssembly package recognises such an environment in a web page only on localhost or on a subdomain of a covered website; for staging on another domain, ask us.

A license covers installations run by you, or by a contractor for you. A license for a client's website or service names the client as its licensee.

4. What a license lets you do#

• Use the Engine on the installations it covers, for any lawful purpose, in your own websites and online services, including ones you sell to your customers.
• Serve the WebAssembly package to the visitors of a covered website, as part of that website.
• Keep copies of the Engine in your own package and container registries and in your backups.
• Print any number of pages. What you print is yours; we claim no rights in it.

5. What you may not do#

• Distribute the Engine, or make it available for others to install, apart from serving the WebAssembly package as part of a website you run. Putting the Engine inside software that others install (a desktop or mobile application, an appliance, a library, an SDK) needs a separate written agreement with us.
• Offer others a service, library or API whose main purpose is turning HTML, templates or documents they supply into PDF or images, under any name, unless we agree in writing. A product that makes its own documents for its users (their invoices, reports, documents made in your application) is not such a service, even when it is reached through an API.
• Remove, hide or change the mark, or work around, disable or tamper with the license check.
• Use your license, its tokens or your API key to print without the mark anywhere except your covered installations and the environments of §3, or give your API key or a token to anyone but your employees and contractors. (The license key itself is public: it is written into the pages of a covered website.)
• Reverse engineer, decompile or disassemble the Engine, except to the extent the law that applies to you allows it despite this restriction.

If you run more installations than your licenses cover, you will buy licenses for them, from when they began, within 30 days after we ask. We may ask you to confirm in writing how many installations you run.

6. The license check#

The Engine prints without the mark only with a token we sign. It gets the token from api.reflowpdf.com with your license key (on a server, also your API key), keeps it, and checks it without contacting us. A token lasts at most 42 days and at most seven days past the paid period; the Engine asks for a new one before it ends. While a failed renewal is being retried, tokens last seven days. Use in the seven days after a paid period is covered by your license. If the Engine cannot reach us, it keeps printing without the mark until its token ends; for a machine without network access, fetch a token yourself (GET https://api.reflowpdf.com/v1/engine/license?key=… with your API key) and give it to the Engine. The check is not a lock: these terms, not the check, decide what you may do.

If we stop issuing tokens during a period you have paid for, we will give you a token for the rest of it, or refund the unused part.

7. Subscription, renewal and refunds#

A license is billed monthly or yearly through Stripe and renews until you cancel it. You can cancel at any time in Billing (Engine licenses → Billing and invoices); the license stays active until the end of the period you have paid for. If you ask within 14 days of the first charge for your first license, we refund that charge in full and the license ends; stop using the Engine without the mark from then. Other charges are not refundable. Nothing here limits refund rights you have under the law. We may change prices; a change applies to your license at its first renewal at least 30 days after we tell you by email, and you can cancel before it does.

8. Updates and support#

While your license is active you receive the Engine's updates. Start includes support by email; Business includes a reply from us within one business day (Monday to Friday, United States Eastern time) and early builds.

9. What the Engine sends to us#

The Engine prints on your systems and sends none of your documents to us. It contacts api.reflowpdf.com only to (a) get a token, sending your license key (on a server, also your API key); (b) for a licensed Engine, get a printer profile or a catalogue font a document names, sending the token and that name; (c) if you load the Engine's files from our address, get them. In a web page these requests come from your visitor's browser and carry its IP address and your page's origin; the token is kept in the browser's local storage. What we keep and for how long is in our Privacy Policy (https://reflowpdf.com/privacy).

10. Printer profiles#

FOGRA39.icc, CGATS21-2-CRPC5.icc and CGATS21-2-CRPC6.icc, which the program carries and the WebAssembly package fetches from us, are printer profiles we built from published characterization data: FOGRA39 from Fogra's FOGRA39L (www.fogra.org), the two CRPC profiles from the ISO 15339-2 data sets of ISO TC 130. Fogra and ISO are the sources of that data and do not certify, approve or endorse the profiles. The profiles are ours and licensed to you with the Engine.

U.S. Web Coated (SWOP) v2 (Copyright 2000 Adobe Systems, Inc.) is Adobe's. A licensed WebAssembly package fetches it from us, unaltered, when a document claims PDF/X for CGATS TR 001; you may use it under the Adobe Color Profile License Agreement in THIRD-PARTY-NOTICES.md. We disclaim, on behalf of Adobe, all warranties and conditions, express or implied, and exclude all liability of Adobe for damages, as to the profile. Any provisions of this license that differ from Adobe's agreement are offered by us alone and not by Adobe. The profile is available from us (GET https://api.reflowpdf.com/v1/output-intents/CGATS%20TR%20001/profile with your API key or license token) and from Adobe. The program does not carry it: for that condition it uses a profile you obtain yourself and place in share/reflowpdf/icc, under the terms you obtained it under.

11. Ending the license#

If you break these terms and do not fix it within 30 days after we tell you, we may end your license; if you work around the license check or distribute the Engine against §5, we may end it at once. When a license ends, stop using the Engine without the mark on the installations it covered. Sections 5, 10, 12, 13 and 16 survive the end of a license.

12. No warranty#

THE ENGINE IS PROVIDED "AS IS" AND "AS AVAILABLE", WITHOUT WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT, TO THE MAXIMUM EXTENT PERMITTED BY LAW. We do not promise that what the Engine prints meets any standard or law (PDF/UA, PDF/A, PDF/X, accessibility laws); check it for your purpose.

13. Limitation of liability#

To the maximum extent permitted by law, INSEAW LLC and its members will not be liable for any indirect, incidental, special, consequential or punitive damages, or for any loss of data, profits or business, arising from your use of the Engine. Our total liability for any claim relating to the Engine is limited to the amount you paid us for it in the twelve months before the claim arose.

14. Changes to these terms#

We may change these terms. For a license, a change applies from its first renewal at least 30 days after we tell you by email; you can cancel before then. Without a license, the version that comes with the copy you use applies.

15. Notices, transfer and the rest#

We send notices to the email of the account the license belongs to; send yours to hello@reflowpdf.com. You may transfer a license only with the sale of the business or product that uses it, after telling us in writing; we may transfer these terms to a successor of our business. You will not use, export or re-export the Engine in breach of United States export control or sanctions laws, or others that apply to you. The Engine is commercial computer software (48 C.F.R. 2.101); the United States Government receives only the rights in these terms. If part of these terms is unenforceable, the rest stays in force and that part applies as far as the law allows. These terms, with any written agreement we sign with you, are the entire agreement about the Engine.

16. Governing law#

These terms are governed by the laws of the State of South Carolina, without regard to its conflict-of-laws principles; the United Nations Convention on Contracts for the International Sale of Goods does not apply. Any dispute arising out of or relating to these terms or the Engine will be brought exclusively in the state or federal courts located in South Carolina, and each party consents to the personal jurisdiction of those courts.