Guides

Practical write-ups on the things people most often get stuck on with QR codes and file conversion.

QR codes

How to make a Wi-Fi QR code
Let guests join by scanning instead of typing a password — and where it is safe to display one.
How to read a QR code from an image
Decode a code from a screenshot or photo, and check where it leads before you trust it.
Static vs dynamic QR codes
Why dynamic codes stop working when a subscription lapses, and how to get editability without the dependency.
QR error correction levels explained
What L, M, Q and H actually do, and which to pick for print, outdoors, or a code with a logo.

How to convert HEIC to JPG
iPhone photos that Windows and Android refuse to open, fixed — and how to stop your phone making them.
How to convert WebP to PNG
That image you saved from a website which nothing will open. Also when to keep it as WebP.
How to make a favicon (.ico)
Build a multi-size icon from a PNG, plus the HTML that makes browsers pick it up.
How to combine images into one PDF
Turn a pile of phone photos of paperwork into one document somebody will accept.

How to merge PDF files
Combine, split, extract a page range or rotate — without handing a contract to a random website.
How to convert a PDF to images
PNG or JPEG, choosing a resolution, and why text extraction fails on scanned documents.
How to convert DOCX to Markdown
What survives the conversion from Word, what cannot, and the cleanup to expect.

How to convert CSV to Excel
Why opening a CSV directly in Excel destroys leading zeros and turns product codes into dates.
How to convert JSON to YAML
Config files, both directions — including the Norway problem and why comments vanish.
How to convert M4A to MP3
Voice memos and iTunes audio for players that only want MP3, plus lifting audio out of a video.

All of these use the free QR generator and file converter, which runs entirely in your browser — no account, no uploads.