Guides
Practical, no-fluff guides for developers and writers. Each one walks through a real task and points you at the free browser-based tools that get it done, with nothing uploaded anywhere.
What is a cron job and how do you read one
A cron job runs on a repeating clock schedule set by a five-field expression like 0 9 * * 1-5. How to read each field, with a free explainer to check it.
Best free Wi-Fi QR code generator
Paste a WIFI: payload to make a Wi-Fi QR code. The password is encoded locally, the PNG is static and never expires, and it costs nothing.
Why does my URL show %2520
%2520 is not corruption: it is a space percent-encoded twice, first to %20 and then again. Why double encoding happens and how to decode it per layer.
Best free word counter for students
Live word and character count the moment you paste, so you can check an essay against a limit. No account, no ads on the tool, and nothing is uploaded.
Best free online UUID generator
Generate 1 to 100 version 4 UUIDs from your browser's secure random source, with one-click copy. Free, no signup, and nothing is sent to a server.
JPG vs PNG: what is the difference
JPG is lossy and tiny, best for photographs. PNG is lossless with transparency, best for logos, screenshots and text. How to choose, then compress.
Best free online regex tester
Highlight matches and capture groups in real time with all six JavaScript flags exposed. Free, no signup, and your pattern never leaves the browser.
Best free diff checker for code review
Highlight every added and removed line between two versions instantly. No ads, no account, and nothing leaves your device, so pasting work code is safe.
Why is my JWT invalid
Four usual causes: malformed (not three Base64URL parts, or a leftover Bearer prefix), expired, a signature that will not verify, or not yet valid.
Why is my SHA-256 hash different
SHA-256 is deterministic, so two results mean two inputs: a trailing newline, CRLF endings, a text-encoding mismatch, or uppercase versus lowercase hex.
SHA-1 vs SHA-256: what is the difference
SHA-256 has no known practical collision; SHA-1 was broken by a real collision in 2017 and NIST disallows it after 2030. Why that matters in practice.
Best free online binary to decimal converter
Convert binary to decimal, and to octal and hex at the same time, with exact BigInt arithmetic. Free, no signup, and it runs entirely in your browser.
Best free lorem ipsum generator for designers
Generate placeholder paragraphs, sentences or words with one-click copy. Free, no account, nothing to install, so you can fill a mockup in seconds.
Best free online URL encoder and decoder
Percent-encode any value, decode it back to plain text, and get told when the input is malformed. Free, no signup, and it runs entirely in your browser.
UUID vs GUID: what is the difference
They are the same thing: a 128-bit ID in 8-4-4-4-12 format. UUID is the RFC 9562 standard, GUID is Microsoft's name. The only real gap is byte order.
Why is my Base64 decode showing garbled text
Garbled Base64 is rarely broken Base64. You decoded the bytes correctly but read them with the wrong character set, or used URL-safe input on a decoder.
Best free case converter for developers
Convert text to camelCase, snake_case, kebab-case and four more styles instantly, with a live toggle and one-click copy. Free, no account, no upload.
Best free online hex to decimal converter
Convert hex to decimal, and to binary and octal at once, with exact BigInt arithmetic so large values stay precise. Free, no signup, runs in your browser.
Why is my regex not matching
Usually the global flag advanced lastIndex, a special character was not escaped, or a flag such as ignore-case was off. How to spot each one live.
Best free color palette generator for web design
Turn one base color into complementary, triadic and analogous schemes with copy-ready hex codes. Free, no account, instant color theory in the browser.
HTML entities vs URL encoding: the difference
Both replace unsafe characters, but they solve different problems: HTML entities protect markup, percent-encoding protects URLs. When to use each.
Why is my Unix timestamp showing 1970
A timestamp reads as 1970 when a near-zero or wrongly scaled value is measured against the epoch. How to tell seconds from milliseconds and fix it.
Best free online SHA-256 hash generator
Hash text with the native Web Crypto API and get SHA-1, SHA-256, SHA-384 and SHA-512 side by side. Free, no signup, and nothing is uploaded.
Best free slug generator for SEO-friendly URLs
Turn any title into a clean lowercase hyphenated URL slug. Deterministic, so it keeps your exact words instead of rewriting them. Free, no account.
Encoding vs encryption vs hashing: the difference
Encoding is reversible with no key, encryption is reversible only with a key, and hashing is one-way. What each one is actually for, with examples.
Best free image compressor for email attachments
Shrink a JPG or PNG with a quality slider until it fits Gmail, Outlook or Yahoo limits. Live before-and-after sizes, and your photo never leaves the page.
How to fix Unexpected token errors in JSON
Paste the text into a JSON formatter, read the line and column it reports, then check the character just before it. The seven causes, and how to fix each.
Why is my QR code not scanning
Nine usual causes: too small, too dense, low contrast, inverted colors, no quiet zone, blur, a dead redirect, a typo, or screen glare. Each one fixed.
Base64 vs Base64URL: what is the difference
Base64URL is Base64 with three swaps: - for +, _ for /, and padding usually dropped, so values survive URLs and filenames. Convert both ways free.
Free alternative to base64decode.org
Converts text locally with no ads and no server round-trip, even when decoding. Where base64decode.org is still the better pick, stated honestly.
Free alternative to UUIDGenerator.net
Creates version 4 UUIDs locally with no ads and no server round-trip. Where UUIDGenerator.net is still better, including v1, v7 and file downloads.
Free alternative to Diffchecker
Both are free, so the real differences are no ads, a comparison that never leaves your device, and a tool that keeps working offline. An honest look.
Free alternative to WordCounter.net
Counts words, characters, sentences, paragraphs and reading time live, with no ads. What WordCounter.net still does better, stated honestly.
Free alternative to regex101
For quick JavaScript regex testing: live match highlighting, capture and named groups, no sponsor banner. Where regex101 remains the stronger tool.
Free alternative to epochconverter.com
Converts epoch seconds or milliseconds to UTC and local dates and back, with no signup. What epochconverter.com still does better, stated plainly.
Best free password generator that works offline
Build passwords with crypto.getRandomValues that keep working after you lose your connection. No ads, no account, and nothing ever leaves the page.
Best free QR code generator that doesn't expire
Static QR codes are yours forever, with no account and no trial clock. Nothing to renew, no redirect to go dead, and the code is built in your browser.
Free alternative to jwt.io
Reads a JWT header and payload instantly with no signup and no identity-platform marketing. What jwt.io still does better, stated honestly.
Free alternative to TinyPNG
Shrinks JPG and PNG locally with a quality slider, with no 20-image batch limit and no 5 MB file cap, and your images are never uploaded anywhere.
Free alternative to JSONLint
Both are free, so price is not the difference. No third-party ads, an interface that works offline, and where JSONLint is still the better choice.
Best free online JSON formatter that works offline
Validate and pretty-print JSON with no connection at all, because the formatting logic lives in the page itself. Free, no signup, nothing is uploaded.
JSON Formatting vs Minifying: When to Use Each
Learn when to pretty-print JSON for debugging and when to minify it for production, plus how validation and indentation actually work.