Tax Analyzer

This tool gives you a detailed slab-by-slab breakdown of the taxes owed by an unmarried individual living in New York City. This tool is written in ReasonML, and uses ReasonReact and Recharts.

How to Use

Click here: https://arjun-menon.com/tax-analyzer/

Building

To set up and install dependencies, run:

npm run init
npm install

During development, run:

npm run watch
# in another tab:
npm run serve

Both are long running commands, that will monitor the filesystem for changes, and automatically rebuild.

To generate a production-optimized JS artifact, run:

npm run bundle

The base ReasonML template for this was this.

A bit of history

This project was started on May 31, 2014. Back then, this was just a Python script (an early commit). It was later rewritten in JavaScript (some early commits), and a web UI was added that was written in pure vanilla JS (a commit, and the index.html at the time). It was later rewritten entirely in ReasonML in 2019 (e.g. a commit). Lastly, since ReasonML went through some changes after the BuckleScript / ReScript split, I migrated it over to new tooling over 2024 and 2025 as well (PR).

You can see how things looked like in the UI back then (pretty similar to today):

Caveats

The purpose of this web app is to just get a rough analysis of the taxes you owe. It doesn't cover things like:

• Alternative Minimum Tax: if you have a high income and take a large number of tax deductions, you may be subject to the Alternative Minimum Tax.

• Personal Exemptions Phase-out: personal exemptions are reduced with higher incomes, and eventually phased out. This is no longer relevant after 2018, since the tax reform passed in December 2017 eliminated federal personal exemptions.

• New York State restrictions on itemized deductions for high-income earners.

• Tax Credits, federal and state.

  • New York State and New York City both offer a variety of credtis, see:

    • New York State Credits
    • New York City Credits

    For example, most single NYC residents qulify for the school tax credit (form NYC-210, instructions). Lower incomes make one eligible for a wide variety of credits such as the NYS Household Credit, the NYS earned income credit, the federal EITC, the federal Saver's Credit, etc.