Guides
Practical write-ups on how these tools work, when to use them, and what to watch out for. Same rules as the tools themselves — no uploads, no sign-up.
Are Online File Converters Safe? What Actually Happens to Your Files
When you upload a file to an online converter, where does it go and how long does it stay? Here is the real pipeline, the risks that matter, and how to check any tool yourself.
How to Compress Images Without Losing Quality
Compression is not the same as degradation. Here is what actually controls image file size, which targets to aim for by use case, and how to compress images in your browser.
How to Add a Favicon to Your Website (Every Size, Done Right)
A favicon is the smallest piece of design on your site and the one users see most. Here is the full set of sizes you actually need, how to survive 16 pixels, and the caching trap that makes you think it did not work.
How to Build a Color Palette (and Convert Between HEX, RGB, and HSL)
Extracting colors from an image is the easy part. Here is how to turn them into a palette that actually works, and why HSL is the format to think in even when you ship HEX.
How to Clean Up Text Before You Publish It
Word counts, title case, URL slugs, placeholder text, and encoding — the small text decisions that decide whether a page reads as considered or careless. Here is how to get each one right.
How to Convert HEIC to JPG on Windows, Mac, iPhone, and Android
iPhone photos are HEIC files that many apps refuse to open. Here is how to convert them on every platform, how to batch convert, and what to do afterwards.
How to Convert a Video to GIF (and When You Should Not)
GIFs are the only animation format that works everywhere, and the most expensive one to ship. Here is how to make one, how to keep it small, and when a video is the better answer.
How to Convert Word and Excel Files to PDF (Without Uploading Them)
Word documents and spreadsheets are the two file types people convert to PDF most often. Here is what the conversion really does, what survives it, and how to do it without handing your file to a server.
How to Create a Strong Password You Can Actually Remember
Length beats complexity, and most password advice you have been given is out of date. Here is what actually makes a password hard to crack, and how to generate one safely.
How to Extract Text From an Image (Screenshots, Scans, and Photos)
Text inside a picture cannot be copied, searched, or edited — until OCR turns it back into characters. Here is how OCR works, what makes it accurate, and how to get the best result from a bad image.
How to Format, Validate, and Convert JSON
Minified JSON is unreadable, invalid JSON is worse. Here is how to format and check it, the errors that break it most often, and how to move data between JSON and CSV.
How to Merge and Split PDF Files Without Uploading Them
Combining PDFs is a five-second job that most tools make you upload for. Here is how to merge, split, compress, and convert PDFs entirely in your browser.
How to Read and Convert Unix Timestamps (and Write Cron Correctly)
A Unix timestamp is a count of seconds since 1970, and most bugs involving it come down to two things: seconds vs milliseconds, and timezones. Here is how to read one, convert it, and schedule with cron without surprises.
How to Use Text to Speech in Your Browser (and What It Cannot Do)
Browser text-to-speech runs on voices already installed on your device, which makes it instant and private — and also means it cannot hand you an audio file. Here is what it does well and where it stops.
How to Write and Test a Regular Expression Without Losing Your Mind
Most regex pain comes from two things: thinking of it as text search instead of pattern description, and never checking what it does on input that should not match. Here is the mental model and the traps.
QR Codes vs Barcodes: What the Difference Actually Is
One is a row of numbers, the other is a grid that can hold a URL. Here is what each format can store, when to use which, and the security problem nobody mentions.