OptionWit for teachers
A free options calculator for the classroom, no signup, nothing stored
OptionWit is a free Black-Scholes option calculator that reprices an option across every future date and stock price on a single board, with the Greeks, breakeven, and expected move alongside it. It is built to make the mechanics visible, which is exactly what a class needs. You are welcome to use it in teaching, and this page shows how.
Free, and friendly to a classroom
- No signup and no accounts. Students just open the page and start. There is nothing to install and no license to manage.
- Nothing is stored and there are no cookies. Everything runs in the browser, so it works on locked-down school devices and respects student privacy. Analytics are cookieless page counts only.
- Every number is reproducible. The pricing engine is open source with a test suite that pins each figure, and the methodology page states the exact formulas. Students can check the model, not just trust it.
- Shareable scenarios. The full setup is encoded in the URL, so you can hand out a link that opens the exact example you want to discuss.
Embed it in your course page
Drop the calculator straight into a syllabus page, an LMS page, or a lecture site with one iframe. It is responsive and links back to OptionWit.
See the embed guide for options, or preview the widget your iframe will show.
A ready-to-run exercise: predict Monday's value
This mirrors the "what will my option be worth on Monday?" guide and takes about ten minutes. It teaches theta (time decay) with numbers students verify themselves.
Time decay over a weekend
- Open the calculator. It loads the default example: a $105 call on a $100 stock at 45% implied volatility with 30 days to expiry. The model value is $3.27 and theta is -$0.087 per day.
- Predict. Ask students: if the stock does not move, what is the option worth three days from now? Using theta, the estimate is 3.27 - 3 × 0.087 = about $3.01.
- Check. Change days to expiry from 30 to 27 and read the new model value. It is $3.01, right on the estimate, because 30 days out theta is nearly constant from day to day.
- Break it. Now set days to expiry to 5 and repeat the three-day prediction. The simple theta estimate no longer holds, because theta accelerates as expiry nears. The theta-decay guide shows why, day by day.
Discuss: why is a linear theta estimate fine far from expiry but wrong near it? What does that imply about holding an option into its final week?
Teaching with it? Get in touch
If you are using OptionWit in a course, I would like to hear about it and I am happy to help. Reach out through the contact page with what you are teaching and what would make the tool more useful for students. Suggestions from instructors shape what gets built.