Dev tools · alternatives · 2026
24 alternatives to An API for filling out PDF forms
Fill out and generate PDFs with a simple API request. Design templates in our drag-and-drop editor, POST your JSON data, and download a finished PDF in seconds.
FormAPI is a developer tool that automates PDF form filling through an API. It enables software engineers to programmatically populate, generate, and manage PDF documents with form data. The service is designed for… Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. An API for filling out PDF forms launched in 2017; newer entries below may have overtaken it.
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The easiest way to programmatically populate any PDF
2020 · useanvil.com · its alternatives →
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- 4PO
Fill in PDF templates with the PDF Otter API. Use it to accept eSignatures in your app, repeatedly fill in common PDF forms, or build large scale apps around PDF documents.
2017 · pdfotter.com · its alternatives →
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Anvil PDF API▲185Twilio for PDFs: esign, fill, generate PDFs with one API
2021 · useanvil.com · its alternatives →
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Fillout 2.0▲344All-in-one forms, scheduling, payments & workflows
2024 · fillout.com · its alternatives →
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DocSpring▲12POST JSON; GET PDF - Fill, generate, and sign PDFs via API
2025 · docspring.com · its alternatives →
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PDFShift▲386Convert any HTML to PDF with a single POST request.
2018 · pdfshift.io · its alternatives →
- 10PA
Hi HN, Arek here. We’re super excited to officially launch PSPDFKit API [1]. PSPDFKit API is a collection of HTTP APIs that enable you to convert, generate, and edit documents without running any service on your infrastructure. What differentiates our API from others is that you can chain together multiple “actions” as part of a single API request. For example, you can convert, OCR, watermark, edit, and flatten a document — all in one call. Available actions [2]: - PDF Generator - PDF Converter - Image Converter - OCR - Watermark - Merge - Split - Duplicate - Delete - Flatten Our…
2022 · its alternatives →
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A flexible Web API and template editor for PDF generation
2020 · pdfgeneratorapi.com · its alternatives →
- 13PJ
Hi HN, Nick here. We're super excited to officially launch PDF.js Express [1]. PDF.js Express wraps a modern React UI around the PDF.js rendering engine to enable PDF annotation, form filling, and signing inside your web app. We've also made some improvements to PDF.js text search, and taken a different approach to how the viewer uses the PDF.js rendering API, resulting in sharp graphics at any zoom magnification [2]. Based on our research, more than 70% of those who try to implement these features on top of PDF.js find it too difficult or time-intensive [3]. For those who are successful,…
2020 · its alternatives →
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Documind is an open-source tool that turns documents into structured data using AI. What it does: - Extracts specific data from PDFs based on your custom schema - Returns clean, structured JSON that's ready to use - Works with just a PDF link + your schema definition Just run npm install documind to get started.
2024 · github.com · its alternatives →
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Convert Excel templates into dynamic PDFs
2023 · pdfhippo.com · its alternatives →
- 17AF
2022 · doqs.dev · its alternatives →
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- 19FP
2017 · form.ac · its alternatives →
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Web service to automate PDF form filling
2019 · pdfformfiller.herokuapp.com · its alternatives →
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DocAPI▲4Extract invoices and PDFs into clean JSON with one API call.
Jun 2026 · docapi.site · its alternatives →
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Add text, watermarks, and fill forms in pdfs with ease | API
2025 · prefillpdf.com · its alternatives →
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Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →