Setup

This guide walks you through uploading a workbook and configuring assumptions and outputs so you can run Monte Carlo simulations on your spreadsheet model.

Core concepts

Concept	Description
Workbook	An .xlsx file you upload as the simulation model. Pocketstats renders it in IronCalc — a read-only in-browser spreadsheet engine.
Assumption cell	A cell whose value is replaced by a sampled distribution on each simulation iteration. Highlighted in blue.
Output cell	A cell whose value is recorded after each iteration. Highlighted in green.
Config	A saved set of assumptions and outputs for a workbook. Configs persist across sessions so you don't need to re-configure on each visit.

Uploading a workbook

1. Go to App → Spreadsheet Sim.
2. Click Upload .xlsx in the header.
3. Select an .xlsx file from your computer.

The workbook opens in the IronCalc viewer in the main panel. Sheet tabs appear at the bottom — you can switch between sheets.

note

IronCalc is read-only. You cannot edit cell formulas in the browser. To change the model, edit the file locally and re-upload.

Navigating the layout

The screen is divided into two areas:

Sidebar (left):

• Assumptions list with a + Add button
• Outputs list with a + Add button
• Test runs input (how many times to simulate your spreadsheet — more runs = more reliable results)
• Save Config / Load Config buttons

Spreadsheet (right):

• Full IronCalc workbook view
• Assumption cells are highlighted in blue
• Output cells are highlighted in green

Saving and loading configs

A config stores your list of assumptions and outputs for a given workbook.

To save a config:

1. Click Save Config in the sidebar.
2. Enter a descriptive name for the config.
3. Click Save — the config is saved to your account.

To load a config:

1. Click Load Config in the sidebar. A list of previously saved configs appears.
2. Select the config you want to restore — assumptions and outputs reload automatically.

tip

Use descriptive names (for example, "Q4 forecast — base case") so you can find configs across sessions and distinguish between scenario variants.

Configs are saved to your account and persist across sessions.

Next steps

• Add assumptions — mark cells as inputs sampled from a distribution.
• Run simulations — set test runs, run the model, and view results.

Reference

Config properties

Property	Description
Name	Identifies the config in the Load Config list
Assumptions	Ordered list of assumption definitions (cell reference, distribution, parameters)
Outputs	List of output cell references to record
Test runs	Number of simulation iterations stored in the config

Supported workbook features

Feature	Support
.xlsx files	Supported
Multiple sheets	Supported — switch via sheet tabs
Cell formulas	Rendered read-only via IronCalc
.xls (legacy format)	Not supported — save as .xlsx first
Macros / VBA	Not executed