📋 Developer Cheat Sheets
Quick reference tables for everyday web development. Bookmark this page — it's the only cheat sheet you'll need.
HTTP Status Codes
| Code | Meaning | When to Use |
|---|
200 | OK | Successful request |
201 | Created | Resource created (POST) |
204 | No Content | Success with no body (DELETE) |
301 | Moved Permanently | Permanent redirect |
302 | Found | Temporary redirect |
304 | Not Modified | Cached version is still valid |
400 | Bad Request | Malformed request syntax |
401 | Unauthorized | Authentication required |
403 | Forbidden | Access denied |
404 | Not Found | Resource doesn't exist |
405 | Method Not Allowed | Wrong HTTP method |
429 | Too Many Requests | Rate limit exceeded |
500 | Internal Server Error | Server-side error |
502 | Bad Gateway | Upstream server error |
503 | Service Unavailable | Server overloaded/maintenance |
🔧 HTTP Status Code Tool →
Common Regex Patterns
| Pattern | Matches | Example |
|---|
^\d+$ | Integers only | 42, 123 |
^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$ | IPv4 address | 192.168.1.1 |
^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$ | Email address | user@example.com |
^https?://[^\s]+$ | URL | https://wootils.com |
^#?([a-fA-F0-9]{6}|[a-fA-F0-9]{3})$ | Hex color | #FF5733 |
^\d{4}-\d{2}-\d{2}$ | ISO date | 2026-02-11 |
^(?=.*[A-Z])(?=.*[a-z])(?=.*\d).{8,}$ | Strong password | MyP@ss1! |
\b\w+\b | Words | any word |
🔧 Regex Tester →
CSS Units Reference
| Unit | Type | Description |
|---|
px | Absolute | Pixels (1/96 of an inch) |
em | Relative | Relative to parent font size |
rem | Relative | Relative to root font size |
% | Relative | Relative to parent element |
vw | Viewport | 1% of viewport width |
vh | Viewport | 1% of viewport height |
ch | Relative | Width of "0" character |
fr | Grid | Fraction of available space |
🔧 Unit Converter →
Unix File Permissions (chmod)
| Number | Permission | Symbol |
|---|
0 | No permission | --- |
1 | Execute | --x |
2 | Write | -w- |
4 | Read | r-- |
5 | Read + Execute | r-x |
6 | Read + Write | rw- |
7 | Read + Write + Execute | rwx |
Common: 644 (files), 755 (directories/scripts), 600 (private keys)
🔧 Chmod Calculator →
Common HTML Entities
| Character | Entity | Code |
|---|
| & | & | & |
| < | < | < |
| > | > | > |
| " | " | " |
| ' | ' | ' |
| | |   |
| © | © | © |
| → | → | → |
| — | — | — |
🔧 HTML Entity Encoder →
VS Code Keyboard Shortcuts
| Action | Windows/Linux | macOS |
|---|
| Command Palette | Ctrl+Shift+P | Cmd+Shift+P |
| Quick Open File | Ctrl+P | Cmd+P |
| Find & Replace | Ctrl+H | Cmd+H |
| Toggle Terminal | Ctrl+` | Cmd+` |
| Multi-cursor | Ctrl+D | Cmd+D |
| Move Line Up/Down | Alt+↑/↓ | Option+↑/↓ |
| Duplicate Line | Shift+Alt+↓ | Shift+Option+↓ |
| Comment Toggle | Ctrl+/ | Cmd+/ |
| Format Document | Shift+Alt+F | Shift+Option+F |
Popular CSS Colors
| Name | Hex | Preview |
|---|
| Coral | #FF7F50 | |
| Tomato | #FF6347 | |
| DodgerBlue | #1E90FF | |
| MediumSeaGreen | #3CB371 | |
| SlateBlue | #6A5ACD | |
| Gold | #FFD700 | |
| HotPink | #FF69B4 | |
| DarkSlateGray | #2F4F4F | |
🔧 Color Converter →
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Page Title — Site Name</title>
<meta name="description" content="155 chars max">
<link rel="canonical" href="https://example.com/page">
<meta property="og:title" content="Title">
<meta property="og:description" content="Description">
<meta property="og:image" content="https://example.com/img.png">
<meta property="og:url" content="https://example.com/page">
<meta name="twitter:card" content="summary_large_image">
🔧 Meta Tag Generator →