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These articles are static pages built from Markdown in the repository. They explain concepts and point to tools that run locally in your browser whenever the task allows. Browse by topic or search the full set.
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- Published: 2026-09-05
QR codes: error correction and use cases
How QR error correction levels L, M, Q, and H trade capacity for damage tolerance, when to use Wi-Fi and vCard payloads, and why quiet zone and contrast matter for reliable scans.
Read article → - Published: 2026-09-05
Lossy vs lossless image compression
How JPEG, PNG, and WebP trade quality for file size, when lossless still wins, and how to resize and re-encode photos locally without uploading them.
Read article → - Published: 2026-09-05
Embedding images as Base64 data URLs in CSS and HTML
How data URLs pack image bytes into CSS and HTML, why Base64 inflates size by about 33%, when embeds beat external files, and how to encode images locally without uploading them.
Read article → - Published: 2026-09-05
PNG to favicon.ico and multi-size icon packs
How browser favicons and app icons use multiple sizes, what goes in favicon.ico vs PNG packs, HTML link tags that matter, and how to generate an icon set locally from one square source image.
Read article → - Published: 2026-09-05
Minifying SVG with SVGO profiles in the browser
What SVGO actually changes in SVG markup, how safe vs balanced vs aggressive profiles differ, and when to keep titles, IDs, and dimensions before shipping icons.
Read article → - Published: 2026-09-05
Reading EXIF, GPS, and camera tags from photos privately
What EXIF, IPTC, and XMP store in JPEG and other images, why GPS tags leak location, how camera settings show up in metadata, and how to inspect tags in the browser without uploading photos.
Read article → - Published: 2026-09-05
Generating Code128, EAN, UPC, and QR barcodes offline
When to use Code128 vs EAN-13/8 vs UPC-A vs QR, how GS1 check digits work, quiet zone and contrast tips, and how to generate PNG or SVG barcodes in the browser without uploading payloads.
Read article → - Published: 2026-09-05
PDF merge, split, and trim without uploads
How to combine PDFs, extract page ranges, and drop unwanted pages with 1-based specs—why upload converters are risky for contracts, and how pdf-lib does the same work in the browser.
Read article → - Published: 2026-06-26
MIME types and file extensions
How type/subtype MIME labels relate to dotted file extensions, why HTTP uses Content-Type instead of filenames, and when the same format has more than one valid label.
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