Guides
Plain-language explainers behind the calculators and tools on this site — how the math works, what the numbers mean, and how to read the results.
How Mortgage Amortization Actually Works
Why your early mortgage payments are mostly interest, how the balance tips toward principal over time, and how to read an amortization schedule.
PDF Compression Explained: Why Your File Is So Big
What actually makes a PDF large, how compression tools shrink it without destroying quality, and when compression can't help.