Guides
Plain-language explainers and step-by-step walkthroughs for the everyday problems our tools solve. Written for working developers, designers, and anyone trying to get a small task done well.
How to Compress Images for the Web Without Losing Quality
A practical guide to image compression: which format to choose, what quality level to use, when to resize before compressing, and how to keep type-heavy images from turning to mush.
A Practical Guide to JSON: Formatting, Validating and Converting
JSON is everywhere, but it is easy to get wrong. A field guide to the syntax that trips people up, the difference between formatting and validation, and how to safely convert between JSON and CSV.
How to Create Strong Passwords (and Why Length Beats Complexity)
What actually makes a password strong in 2026, why the old advice about special characters is misleading, and how to use a password generator without falling into common traps.
URL Encoding and Base64, Explained
What URL encoding actually does, where Base64 fits in, why neither is encryption, and the small handful of cases where reaching for the wrong one will break your day.
Understanding Web Colour: HEX, RGB, HSL and How to Convert
Why the same colour has so many notations, what each one is good for, how to read a HEX code at a glance, and a few practical rules for choosing accessible colour pairs.
How to Calculate a Loan Payment, Step by Step
The actual formula behind a fixed-rate loan payment, why your first few payments are mostly interest, what an amortisation schedule looks like, and how compound interest works in your favour on savings.
About these guides
Every guide here is original, written by the team that builds and maintains the tools at Utylo. They are not affiliate posts, sponsored articles, or AI-generated content scraped from elsewhere. They exist because, in answering reader questions over the years, we kept writing the same explanation a hundred different times — and decided a single, careful version was more useful than a hundred half-baked ones.
Guides are dated and revised when the underlying advice changes. If you spot an error or have a topic you would like us to cover, please let us know through the Contact page.