Software Alternatives, Accelerators & Startups

React Engine VS Fillr.app

Compare React Engine VS Fillr.app and see what are their differences

Note: These products don't have any matching categories. If you think this is a mistake, please edit the details of one of the products and suggest appropriate categories.

React Engine logo React Engine

A react render engine for Universal (previously Isomorphic) JavaScript apps written with express, by PayPal

Fillr.app logo Fillr.app

Form Filler & Test Data Manager: AutoFill With Data You Control
  • React Engine Landing page
    Landing page //
    2023-10-02
  • Fillr.app Capture Once, Fill Forever
    Capture Once, Fill Forever //
    2026-06-26
  • Fillr.app You Decide Every Field
    You Decide Every Field //
    2026-06-26
  • Fillr.app Fill From Your Own Data
    Fill From Your Own Data //
    2026-06-26
  • Fillr.app Speaks +60 Languages
    Speaks +60 Languages //
    2026-06-26
  • Fillr.app Fill Forms With One Click
    Fill Forms With One Click //
    2026-06-26

Fillr is a form filler and test data manager for Chrome โ€” for when it matters what goes into every field. Save any form as a preset with a rule per field, fill it from your own CSV or Excel rows, and manage all your test data in one place. Realistic generated data (110+ types, 60+ languages) is built in โ€” but you decide where it goes.

Anyone can spray random values into a page. Fillr is for when the data has to be right.

๏ฟฝ EVERY FIELD, YOUR RULES โœ“ Capture any form once and save it as a reusable preset โœ“ Set a rule per field: Generate, Fixed value, Blank, Skip, or Dataset column โœ“ Presets auto-match pages by URL pattern โ€” the right preset surfaces the moment you land on the page (with a picker when several match) โœ“ Preview the fill before you run it โœ“ Unlimited presets, free

๏ฟฝ FILL FORMS FROM YOUR OWN DATA (Pro) โœ“ Link a dataset to a preset, map columns to fields, and fill row by row โ€” sequential with a "row 3 of 20" readout, or random โœ“ Run 50 test cases through the same checkout without typing a single value โœ“ Your edge cases, your real records, your regression rows โ€” not random noise

๏ฟฝ๏ธ A REAL TEST DATA MANAGER โœ“ Import CSV, Excel or JSON โ€” or generate sheets of realistic dummy data โœ“ Edit rows in a spreadsheet grid, organize with tags โœ“ Export any dataset to CSV, Excel or JSON

โšก INSTANT FILL, WHEN YOU JUST NEED VALUES One click auto-fills every field with realistic fake data โ€” names, emails, addresses, phones, dates and more. Zero setup, works on any site, one-click Clear when you're done.

๏ฟฝ 60+ LANGUAGES (Pro โ€” English is free) Generate locale-accurate names, addresses and phone numbers in French, German, Japanese, Arabic and dozens more for international testing.

๏ฟฝ๏ธ POINT-AND-CLICK, 100% NO-CODE A side panel plus a draggable floating bar on the page. Fill, clear, capture, switch presets โ€” no scripts, no selectors, no JSON to edit.

Fillr.app

Website
fillr.app
$ Details
freemium $9.99 / Monthly
Platforms
Web (Dashboard) Chrome
Release Date
2026 June

React Engine features and specs

  • Isomorphic rendering
    React Engine enables both server-side and client-side rendering of React components, providing a seamless isomorphic/universal JavaScript experience. This allows for faster initial page loads and better SEO while maintaining rich client-side interactivity.
  • Express.js integration
    React Engine is designed as a view engine for Express.js, making it easy to integrate React into existing Express-based applications with minimal configuration. It follows familiar Express conventions for setting up view engines.
  • Built-in React Router support
    The library comes with built-in support for React Router, enabling developers to easily set up server-side and client-side routing without complex manual configuration.
  • PayPal backing
    React Engine was developed and maintained by PayPal, which provided credibility and ensured it was battle-tested in a large-scale production environment before being open-sourced.
  • Simplified setup
    The library abstracts away much of the complexity involved in setting up server-side rendering with React, reducing boilerplate code and allowing developers to get a universal React application running quickly.

Possible disadvantages of React Engine

  • Abandoned project
    The repository appears to be no longer actively maintained, with no recent commits or updates. This makes it risky to use in production as bugs and security vulnerabilities may go unpatched.
  • Outdated dependencies
    React Engine was built for older versions of React and React Router. It may not be compatible with modern versions of React (16+, 17, 18) or React Router (v5, v6), limiting its usefulness in current projects.
  • Limited ecosystem support
    The library is tightly coupled to Express.js, meaning it cannot be easily used with other Node.js frameworks like Koa, Hapi, or Fastify, reducing its flexibility.
  • Better modern alternatives
    Modern tools like Next.js, Remix, and Vite with SSR plugins provide far more comprehensive and well-maintained solutions for server-side rendering with React, making React Engine largely obsolete.
  • Limited documentation and community
    The project has relatively sparse documentation and a small community, making it difficult for new developers to troubleshoot issues or find examples and best practices for advanced use cases.

Fillr.app features and specs

  • Presets
    Capture any web form as a reusable preset โ€” refill in one click
  • Filling Rules
    Per-field fill rules: generated data, fixed value, your own data, or skip
  • Datasets
    Datasets module: build, generate, or import rows of test data
  • Your Data
    Fill forms with your own imported data, not just fake values
  • Bulk Data Generation
    Use presets schema to generate bulk of data
  • 60+ locales
    60+ locales for realistic, region-specific test data

Analysis of React Engine

Overall verdict

  • Unable to verify a project specifically named 'React Engine' on GitHub with confidence, as this does not correspond to a widely recognized or well-documented open-source project that I have reliable information about. There may be multiple small or niche repositories using this name, and quality would vary significantly between them.

Why this product is good

  • React Engine is not a commonly recognized name in the mainstream React ecosystem
  • No verifiable consensus data on stars, maintenance status, documentation quality, or community adoption is available
  • Could refer to a personal project, a boilerplate, a rendering engine, or a niche tool - without more context, its quality cannot be assessed
  • Names like this are sometimes used for student projects, abandoned repos, or experimental tools that lack production readiness

Recommended for

  • Not recommended without further verification
  • Developers should search GitHub directly, check star count, last commit date, open issues, and documentation before adopting
  • Best suited for evaluation on a case-by-case basis rather than a blanket recommendation
  • If you have a specific repository URL, sharing it would allow for a more accurate assessment

Analysis of Fillr.app

Overall verdict

  • Fillr.app appears to be a form-filling automation tool designed to save time by auto-completing online forms, applications, and repetitive data entry tasks. Based on available information, it offers a convenient solution for reducing manual typing, though users should verify current features, pricing, and security practices directly on their site before committing.

Why this product is good

  • Automates repetitive form-filling tasks to save time
  • Reduces manual data entry errors
  • Likely offers browser extension or integration for ease of use
  • Can store commonly used information for quick access across multiple sites

Recommended for

  • Job seekers filling out multiple online applications
  • Professionals who frequently complete online forms
  • Small business owners handling repetitive data entry
  • Users looking to streamline online registration and checkout processes

Category Popularity

0-100% (relative to React Engine and Fillr.app)
eCommerce Tools
100 100%
0% 0
Web Forms
0 0%
100% 100
Customer Experience Management
Chrome Extensions
0 0%
100% 100

Questions & Answers

As answered by people managing React Engine and Fillr.app.

What makes your product unique?

Fillr.app's answer:

It leads with control, not random fill. Capture any web form as a reusable preset, set per-field rules (generated, fixed, your own data, or skip), and refill in one click โ€” plus a built-in Datasets module to build, generate, and export test data. A form-filler and test-data manager in one, no code.

Why should a person choose your product over its competitors?

Fillr.app's answer:

Fake Filler only sprays random data; Mockaroo generates data but can't fill forms. Fillr does both โ€” and lets you fill with your own data, with reusable presets, per-field control, and 60+ locales. No scripts.

How would you describe the primary audience of your product?

Fillr.app's answer:

QA engineers and developers who repeatedly test web forms and need realistic, controllable test data. Demo and sales engineers are a natural secondary audience.

Which are the primary technologies used for building your product?

Fillr.app's answer:

Next.js 15, React 19, and TypeScript dashboard; a Manifest V3 Chrome extension built with Vite and supabase for backend

User comments

Share your experience with using React Engine and Fillr.app. For example, how are they different and which one is better?
Log in or Post with

Social recommendations and mentions

Based on our record, React Engine seems to be more popular. It has been mentiond 1 time since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.

React Engine mentions (1)

  • react-engine vs other template engines
    I was wondering to use paypal's React Engine (https://github.com/paypal/react-engine), but I have some doubts:. Source: over 4 years ago

Fillr.app mentions (0)

We have not tracked any mentions of Fillr.app yet. Tracking of Fillr.app recommendations started around Jun 2026.

What are some alternatives?

When comparing React Engine and Fillr.app, you can also consider the following products