Guides & Articles
Practical English notes that go with the free tools. Each guide explains limits and links to a calculator or utility you can run in your browser.
- BMI Is Only a Starting Point | Waist and Body Fat Matter Too
- How to Read BMI Ranges | Formula and Common Myths
- BMR vs TDEE | A Practical Intro to Calorie Estimates
- What Is Compound Interest | Why Time Magnifies Growth
- Monthly Saving and Compound Growth | Long-Term Scenarios
- How Mortgage Payments Work | Amortization Basics
- 30-Year vs Longer Mortgages | Payment and Interest Trade-offs
- How to Create Stronger Passwords | Length and Uniqueness
- Password Security Basics | After a Breach and Before One
- Images Too Large | Quality, Formats, and Compression Order
- Social Image Sizes | Crop for the Platform Before Upload
- Choose Aspect Ratio First | Then Resize for Social Posts
- PDF Merge and Split | Plan Before You Process Files
- Percentages, Discounts, and Change | Avoid Common Errors
- Pomodoro Technique | 25-Minute Focus Sessions Explained
- Is Pomodoro Right for You | Building a Focus Rhythm
- QR Codes That Scan Reliably | Content, Size, and Testing
- Unit Conversion Mistakes | Check Scale and Direction
More detail is also available in Traditional Chinese.