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Eighty one-minute lessons on how markets, options, data and risk work, and short stories from real and imagined traders. Generic concepts only, never a trading method.

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Try it: theta decay

Time is the cost. Watch an option lose it.

Drag the slider from 30 days to expiry down to 0. An at-the-money option is all time value, so you can see exactly what the clock takes.

ILLUSTRATIVE · HYPOTHETICAL · NOT LIVE DATA Illustrative curve of an at-the-money option's value as days to expiry fall from 30 to 0.
Black-Scholes call. Spot 25,000, strike 25,000, IV 14%, interest rate 6.5%. Inputs are examples, not a forecast.

View data table

Source: Black-Scholes model v1.0, hypothetical inputs. Not investment advice.

30 daysExpiry

Option value
0
Value vs 30 days
0%
Lost per day now
0

Decay is not even. It is slow early and fast at the end, which is why the last week of an option's life moves so quickly.

Results are hypothetical and for illustration only. Not a guarantee. Not investment advice.

Model card
Name
Black-Scholes theta decay
Version
v1.0
Purpose
Show what time costs an option, under stated assumptions, for learning only.
Method
Black-Scholes European option, no dividends, constant implied volatility. Spot 25,000, strike 25,000, IV 14%, interest rate 6.5%, call.
Limitations
Ignores changes in IV, skew, transaction costs and taxes. Real option prices differ from the model.
Last reviewed
4 Oct 2026

Use your own numbers

80 lessons. One minute each, one every evening at 7:30.

A Daksh Media series. Daksh Media is the media arm of Daksh Analytics.

How the market is built, how options and data work, how risk works, and how our own heads get in the way. Trader Tales run daily at 5:30 PM, and each ends with one question.

Format
40 to 60 second video with a chart
Scope
Generic concepts only. Never a trading method, never a tip.
Data
Illustrative charts, or data older than three months

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