Open-source web app for equity compensation tax calculations.
Live demo: equitycomp.streamlit.app
Author: Priyanka Upreti — CEPI Equity Compensation Associate (ECA) Candidate
Source: github.com/priyanka-upreti/equitycomp
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A multi-module interactive web app that helps employees + practitioners understand the tax + decision implications of their equity grants. Each module accepts grant details and shows the math step-by-step, with the IRC sections + ASC topics cited inline.
| Module | What it calculates | IRC / ASC reference |
|---|---|---|
| ISO Exercise Modeler | AMT preference, dual basis (regular vs AMT), QD vs DD outcomes at sale | IRC §422, §56(b)(3), §1.421-1 |
| ESPP Calculator | Look-back math, $25K limit, cascading anchor reset, QD lesser-of formula, DD treatment. Auto-fills FMVs from a ticker symbol. | IRC §423(b)(1)–(8), §423(c) |
| §83(b) Decision Tool | Net tax savings vs forfeiture risk, breakeven forfeit probability, Form 15620 filing procedure | IRC §83(b); Form 15620 |
| RSU Vest + Sell-to-Cover | Net shares retained, withholding rates, cost basis tracking | §409A short-term deferral; ASU 2016-09 |
| §16 Form 4 Tracker | 2-business-day deadline + short-swing exposure window | SEC §16(a), §16(b); SOX §403 |
| Rule 701 Sizing Calculator | 12-month cap (greatest of $1M / 15% assets / 15% outstanding), rolling-window testing, $10M enhanced-disclosure trigger | Securities Act §3(b); Rule 701(b)–(e) |
Most equity comp calculations live in spreadsheets that are hard to share or verify. This is a public, free, open-source alternative that any employee can use to understand their own grants — and any practitioner can use as a quick reference. All math is validated against worked examples in the CEP reference textbooks (Stock Options Book, Selected Issues, Consider Your Options, Equity Alternatives).
This tool is for educational + planning purposes only. It does not constitute tax, legal, or investment advice. Tax outcomes depend on individual facts + circumstances. Always consult a qualified tax professional before making decisions about equity compensation.
- Python 3.11
- Streamlit (UI framework)
- NumPy, SciPy (math)
- pandas (data tables)
- pytest (test suite)
# Clone the repo
git clone https://github.com/priyanka-upreti/equitycomp.git
cd equitycomp
# Create + activate virtual environment
python3.11 -m venv .venv
source .venv/bin/activate
# Install dependencies
pip install -r requirements.txt
# Run the app
streamlit run streamlit_app.pyApp opens at http://localhost:8501.
MIT — free to use, modify, distribute.