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First-party tools built to test what makes small software useful, understandable, and worth returning to.
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21 shownFinance
Compound Interest Calculator
See how savings grow with contributions over time.
Business
Break-Even Calculator
Find the sales volume needed to cover your costs.
Developer
JSON Formatter
Format, validate, and minify JSON in your browser.
Creator
Reading Time Estimator
Count words, characters, and estimated reading time.
Finance
Tax-Equivalent Yield Calculator
Compare tax-free bond yields with taxable investments.
Business
Gross Margin Calculator
Calculate gross profit and gross margin from revenue and COGS.
Finance
CAGR Calculator
Find the annualized growth rate between two values.
Developer
UUID Generator
Generate secure version 4 UUIDs on demand.
Business
Markup vs Margin Converter
Convert between markup and gross margin percentages.
Developer
Timestamp Converter
Convert Unix timestamps and readable UTC dates.
Creator
Aspect Ratio Calculator
Resize dimensions without stretching your image or video.
Finance
Position Size Calculator
Size a trade from account risk and stop distance.
Business
Cash Runway Calculator
Estimate how many months current cash can support.
Finance
Portfolio Return Calculator
Combine asset weights and returns into one result.
Math & Statistics
Percentage Change Calculator
Measure the relative increase or decrease between values.
Creator
YouTube Hook Workshop
Turn a topic into practical opening-hook directions.
Developer
Base64 Encoder / Decoder
Encode or decode Unicode text locally.
Math & Statistics
Standard Deviation Calculator
Summarize the spread of a numeric data set.
Math & Statistics
Sample Size Calculator
Estimate survey responses for a proportion.
Everyday
Unit Converter
Convert common length, weight, volume, and temperature units.
Everyday
Tip & Split Calculator
Calculate a tip and split the total between people.