‍ ‍ Helping readers move from the unknown to the known

Software Available

  1. Simple Memory System - Capture thoughts & reminders - Available on App Store

  2. Pool Water Balance & LSI Calculator - Balance your water - Available on        PLP website

  3. Stock Position Sizer - Know your Risk - Available on PLP website

  4. Battery & Solar Calculator - Available on PLP website

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PLP Software


Prairie Light Press began with books that help people move from the unknown to the known. Our software follows the same idea: practical tools for everyday problems, built to be clear and useful.

Explore the Prairie Light Press software collection below. Each application is designed to make an everyday task simpler, clearer, and easier to manage.

Black background with a logo featuring a laboratory flask, surrounded by text reading 'SET' at the top and 'OF RES' at the bottom.
Icon of a document with a checkmark, often representing a completed or verified file or task.
Advertisement for a simple memory system app showing screens for thinking, setting reminders, and managing a memory inbox with options to capture thoughts, set reminders, and view completed tasks.

Simple Memory System

Thoughts, Tasks, & Reminders

A thought comes to mind. Something needs doing. Capture it now and find it when you need it.

Simple Memory System gives you a straightforward place for thoughts, tasks, and reminders, with large controls and a clean, readable layout.

Simple Memory System
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Pool Water Balance & LSI Calculator

Test Results, Water Balance & Chemical Dosing

Your water looks clear. But is it balanced? Enter your test results to see what’s happening beneath the surface.

The free Pool Water Balance Calculator shows your LSI and helps you understand whether your water is tending toward corrosion or scale. It also helps you work out chemical amounts for your pool’s water volume.

A blue water droplet with a white scales of justice symbol inside, floating above blue waves.
Pool Balance Calculator
An online pool water balance and LSI calculator webpage, showing input fields for pool test results, current water readings, and projected water targets with a low LSI reading of -0.34 and a balanced LSI of -0.12.
A detailed aquatic chemical management and product selection guide, outlining target water parameters, a staged action plan for adjusting alkalinity and calcium hardness, and specific product recommendations for pool water treatment.

Stock Position Sizer

Plan a stock trade with your risk in view. Enter your account size, risk limit, available cash, entry price, and stop price to see how many whole shares fit your plan. Add a target price to estimate potential gain and reward to risk before you trade.

A stock position sizing calculator with input fields for account value, risk per trade, available cash, trade direction, entry price, stop price, and optional target price. It displays suggested whole shares to buy, risk budget, risk per share, estimated risk at stop, position value, shares by risk, shares by cash limit, potential gain at target, and reward/risk ratio. There are buttons for copying trade summary and resetting the example. The page includes a brief explanation of stop price and risk budget, and a footer note about calculator usage.

Trading risk disclaimer: This calculator is a planning tool, not investment advice or a recommendation to trade. Share counts and potential gains and losses are estimates based on the prices and limits you enter. A stop price does not guarantee an exit at that price; market gaps and fast moves can cause a larger loss. Results exclude commissions, fees, slippage, borrowing costs, and taxes. Short sales carry additional risks. Check the figures and your broker’s requirements before placing a trade.

Open Stock Position Sizer

Battery & Solar Calculator

Need to find out how long it will take to charge a battery from solar panels, or a wall outlet?

Or maybe you want to calculate Runtime for a number of devices you want to run during the day, and you want to know how long you can run them all on batteries?

Check out our Prairie Light Press Battery & Solar Calculator.

A solar battery and power calculator webpage showing calculations for daily energy use, solar panel needs, and battery capacity, with fields for peak sun hours, panel size, battery type, and backup days.
Battery & Solar Calculator