Practice option accounting with explicit assumptions
The simulator records hypothetical long and short option lots. Buying decreases cash and adds an option asset; selling increases cash and adds a short liability. At an unchanged mark, either entry leaves model equity unchanged. Changes in those marks create unrealized gains or losses.
How to use the ledger
- Choose an underlying and call or put, then load the chain. The first 250 rows sorted by strike are a partial sample, with only standard 100-share contracts expiring after today retained.
- Select an available expiry and contract. Review the daily-close premium and its source timestamp; the quote columns are context, not the assumed entry fill.
- Enter a whole quantity from 1 to 999 and record a hypothetical buy or sell. This page limits the ledger to 100 open lots. A sell creates an unconstrained short liability; it is not a covered-call or broker-margin workflow.
- Refresh position marks explicitly. Unavailable marks keep their prior value with a warning. Inspect the source time beside each position.
- Close a lot by entering an assumed exit premium. Record Model Equity adds a session observation; the table is not historical backtest data.
What this simulation leaves out
The model has no stock positions, spread execution, exercise, assignment, dividend processing, broker margin, commissions, or slippage. Daily-close entry and manual-exit assumptions may be impossible to execute. Short option losses can exceed the premium received, and short calls can have unlimited loss. Cash shown after short entries is not available buying power.
Expired contracts remain in the ledger until explicitly closed with an assumed price. Missing marks cannot establish actual settlement. You must not interpret paper returns, win rates, or last-known equity as evidence of live profitability.
Local persistence and recovery
Account records are validated before loading and saved together after initialization. Storage failures leave the session in memory and show a notice. Reset requires confirmation; existing legacy keys remain untouched. Export or back up important research separately before clearing browser data.