Guides & Explainers — Page 4
Practical articles on image compression, PDF workflows, developer tools, and more. Written by Hasanur Rahman — the developer who built the tools.
Showing 61–80 of 94 articles
How to Do a DNS Lookup Online Free
DNS — the Domain Name System — is the phonebook of the internet. It translates human-readable domain names like example.com into IP addresses that computers use to route traffic. When something breaks — email not delivering, website unreachable, SSL errors — DNS records are often involved. This guide covers what the main DNS record types do and how to inspect them with a free online lookup tool.
Read article →How to Resize an Image Without Losing Quality
Resizing sounds simple — change the numbers, get a smaller file. Done wrong, faces turn soft and text becomes unreadable. Done right, you reduce dimensions and file size with no visible quality change at the size you actually need. The difference is direction, algorithm, and target dimensions.
Read article →How to Check Domain WHOIS Information Free
WHOIS is a public database of domain registration information. Every registered domain has a WHOIS record containing the registrar, registration dates, and — unless the registrant uses privacy protection — contact details for the domain owner. This guide explains what WHOIS is, what you can learn from it, and how to look up any domain for free.
Read article →How to Convert RAW Photos to JPG Free
RAW files capture maximum sensor data for editing flexibility, but almost nothing accepts RAW for sharing, printing, or web upload. You need JPG for those workflows. Professional converters cost money and take time to learn. A free browser-based RAW to JPG tool converts camera files in seconds without installing Lightroom.
Read article →HEIC vs JPG — What's the Difference and When to Convert
If you've sent photos from an iPhone to someone on a Windows PC and they couldn't open them, you've already encountered the HEIC problem. HEIC is Apple's default photo format starting with iOS 11 and macOS High Sierra. It's technically superior to JPG in several ways, but compatibility outside Apple's ecosystem is still limited enough to cause real frustration.
Read article →How to Minify JavaScript Online Free
JavaScript minification is a standard step in every web production build. A single JS bundle for a modern web app can easily be hundreds of kilobytes. Minification strips comments, removes whitespace, and shortens variable names to produce a functionally identical but significantly smaller file. Less bytes to download means faster page loads — and faster pages rank better and convert better.
Read article →How to Crop Images Online Without Photoshop
Cropping removes unwanted edges and reframes the subject. You should not need a $600 desktop app for that. Online croppers run in the browser, let you draw the exact area you want, and export in seconds — with your image staying on your device throughout.
Read article →What Is a Hash Function — SHA256 and MD5 Explained
A hash function takes any input — a word, a file, a billion-character string — and produces a fixed-length output called a hash or digest. The same input always produces the same hash. Change one character of the input and the hash changes completely. This behavior makes hash functions essential for verifying data integrity, storing passwords, and digital signatures.
Read article →How to Convert a PDF to Word Free
Converting a PDF to Word is one of the most requested document tasks. You need to edit a contract, update a report, or reuse content from a PDF that was created by someone else. The conversion works well for most documents — but understanding its limitations helps you get a good result every time.
Read article →How to Minify CSS Online Free
Every byte that a browser has to download before rendering your page costs time. CSS files are often full of comments, whitespace, and long property names that are necessary for writing and maintaining code but completely unnecessary for the browser to parse. Minification strips all of that out without changing what the CSS does. Here's how to do it in seconds.
Read article →How to Decode and Inspect a JWT Token Online
JWTs — JSON Web Tokens — are the standard mechanism for passing authentication information between a client and server in modern web applications. If you've ever looked at an HTTP request header and seen a long string starting with 'eyJ', that's a JWT. They look opaque, but they're actually structured data you can read. This guide explains how to decode and inspect a JWT and what each part means.
Read article →How to Reorder Pages in a PDF Free
Pages in a PDF sometimes end up in the wrong order — scanned documents where pages were fed incorrectly, PDFs assembled from multiple sources, or documents where someone moved content around. Reordering pages is a drag-and-drop task that takes less than a minute online, for free.
Read article →How to Convert HEIC to JPG on Android
HEIC is Apple's default photo format on iPhones. It saves storage and preserves quality, but Android phones and many apps cannot open HEIC files natively. If someone AirDropped or messaged you iPhone photos that will not open, converting HEIC to JPG fixes the problem in seconds — no app store download required.
Read article →How to Delete Pages from a PDF Free
Blank pages, cover sheets, disclaimers, or pages that simply don't belong in the version you want to share — deleting specific pages from a PDF is a common cleanup task. You can remove any page you want for free in your browser, with no account needed and no upload.
Read article →How to Resize an Image for Instagram
Instagram crops and compresses every image you upload. If your file is the wrong dimensions or aspect ratio, the app cuts off faces, chops text, or adds unwanted borders. Resizing to Instagram's recommended sizes before you upload keeps your content looking exactly how you designed it.
Read article →How to Extract Pages from a PDF Free
When you only need a few pages from a large PDF — a specific clause from a contract, a single chapter from a report, or a handful of exhibits — extracting those pages into a new file is cleaner than sending the whole document. You can do it for free in your browser in about 30 seconds.
Read article →How to Rotate PDF Pages Online Free
Scanned documents often come out sideways. PDFs created from photos can have pages in the wrong orientation. Fixing page rotation is a quick task that you can do for free in your browser — rotate one page, a few pages, or all pages at once.
Read article →How Image Compression Works — The Plain English Version
Image compression is one of those things most people use constantly without thinking about how it works. You drag a photo into a compressor, a smaller file comes out, and it looks roughly the same. What actually happened in those few milliseconds? This guide explains the mechanics clearly — no maths degree required.
Read article →How to Generate a Strong Password Online
Weak passwords are still one of the leading causes of account compromises. Using 'password123' or a variation of your name and birth year leaves accounts exposed to dictionary attacks in seconds. A strong password is long, random, and unique to each account. Generating and managing strong passwords doesn't have to be complicated — here's what you need to know.
Read article →How to Add Page Numbers to a PDF Free
Page numbers make long PDFs much easier to navigate and reference. Whether you're numbering a report, a thesis, a legal document, or a manual, adding page numbers is a simple formatting step that many PDF tools charge for. You can do it for free in your browser.
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