The Andev blog
Guides, how-tos and notes on privacy-first software and our apps.
How to Convert PDF to Word (.docx) for Free
Turn a PDF into an editable Word document right in your browser — no upload, no sign-up. Here's how it works and when it works best.
Merge PDF Files Privately in Your Browser
Combine PDFs without uploading them anywhere. Here's how in-browser merging works, why it's safer, and how to do it in seconds.
How to Compress Images Without Losing Quality
Shrink image file sizes by 70-90% without visible quality loss. Learn lossy vs lossless, the right quality setting, WebP, and a resize-first workflow.
What Is Spaced Repetition and Why It Works
How spaced repetition fights the forgetting curve using active recall and FSRS scheduling — plus practical tips to remember more in less time.
Why We Build Privacy-First, No-Upload Tools
Most free online tools upload your files to a server. Ours run entirely in your browser, so your data never leaves your device. Here's why.
How to Split a PDF (and Extract Just the Pages You Need)
Split a PDF or pull out a page range in your browser — no upload, no page limits. Here's the page-range syntax and the step-by-step.
Does Daily Brain Training Actually Work?
What the research really says about brain games — and how a calm, consistent daily practice can sharpen working memory, attention and processing speed.
How to Find Your Exact GPS Coordinates
Get your precise latitude and longitude in seconds. Learn what GPS coordinates mean, DD vs DMS formats, and how to read your location from any browser.
How to Use a Mortgage Calculator (and Read It)
Learn how a mortgage calculator turns price, rate, and term into a monthly payment — and how to read amortization so the numbers actually make sense.
How to Format and Validate JSON
Learn how to format, minify, and validate JSON, fix the most common syntax errors, and read parse messages — all privately in your browser.
How to Create a Strong Password (the Right Way)
Strong passwords come from length and randomness, not symbols. Here's what actually works, the length-vs-complexity myth, and a practical checklist.