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Guides to image formats and the tools that handle them, written from the code that runs them. Every number measured, every screenshot from a real run.
How to convert a JPG to PDF without uploading it anywhere
What actually happens when an image becomes a PDF page: the page size, the print DPI and the re-encode nobody mentions. With measured numbers from a real conversion.
What size should an image be for Instagram?
The four Instagram shapes worth targeting, why every one of them is 1080 pixels wide, and what to fix in your export before the platform re-encodes it.
How do I upscale an image to 4K for free?
4K is 3840x2160. Here is what a model reconstructs, what a resizer interpolates, the source width you need and the hardware ceiling that decides if it runs.
How do I resize a JPG to under 100 KB?
The measured quality ladder for one 538.6 KB photo, why the slider stalls at 131 KB and why cutting pixels is the lever that actually hits a byte budget.
Why won't Windows open my iPhone HEIC photos?
Windows needs two separate Microsoft Store components to read a .heic file. Here is what each one does, and how to convert to JPG in a browser tab with neither.
How do I make a favicon package from a PNG without signing up?
The seven files our icon generator writes from one PNG, what reads each one, where they go on your server and why transparent parts come out solid.
PNG vs JPG: which one should you actually save?
Lossless versus lossy, the alpha channel JPG doesn't have and the chroma subsampling that blurs text, with measured file sizes from both formats.
How do I remove an image background for free with no watermark?
What the IS-Net model does inside your browser tab, why the cutout is always a bigger PNG and how to get that PNG back down, with measured numbers.
Is WebP actually smaller than JPG for website images?
We compared JPG, WebP and AVIF on the same 538.6 KB photo at the same slider, and JPG won. Here is why that happens and what the fair comparison shows.
What size is a 2x2 passport photo, and what can a resizer actually check?
How to produce a 600 x 600 passport photo in the browser, why 300 DPI isn't stored in the file and which compliance rules a resizer cannot check.
How do I convert an SVG to PNG without losing the fonts?
Why SVG to PNG output lands at 2x the declared size, and why the browser sandbox silently drops external fonts and linked images during the render.
Image scaler: do you want an upscaler or a resizer?
A resizer interpolates pixels and an upscaler reconstructs them. Which one you need, with measured 2x and 4x results and the real browser limits.
How do I compress a batch of photos for email?
Get a batch of photos under Gmail's 25 MB cap by resizing first and compressing second, with measured before-and-after sizes from our own tools.
Do I still need a favicon.ico, or is PNG enough?
ICO is a directory format that packs 16, 32 and 48 into one 4.6 KB file. What's inside it, why PNG doesn't replace it and the seven files to ship.
How many images can I batch convert in a browser tab?
What a browser batch really costs: 10 files and 50 MB per run, one file at a time, and an AVIF encode that takes 10 seconds each.
How do I extract text from a screenshot without uploading it?
What browser OCR actually reads: measured similarity on six fixtures, the 515 characters it invented from a photo with no text in it and the model download you pay for once.
How do I extract text from a PDF without uploading it?
A digital PDF gives up its text exactly and a scan has to be recognized. Which one you have, what six measured fixtures did, the 25-page cap and the download you pay for either way.