DEVDUNIA
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Full tool: JSON beautifier →
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Free tools
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— tools
POW!
💡 Deep dives — backend internals
How X Works
Step-by-step visual explainers of what really happens under the hood — every actor, every packet, every decision.
google.com — 3D journey
Drag, zoom, and click through a playable 3D map of the internet — DNS, TCP, TLS, and HTTP packets flying in real time
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DNS museum
DNS concepts explained in a comic-book interactive format
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You type a URL
DNS → TCP → TLS → Load Balancer → App Server → DB → response — every hop visualized
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Rate limiting
Token bucket, leaky bucket, sliding window — all 4 algorithms with live interactive demos
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Uber nearby drivers
Geohash, Redis GEORADIUS, H3 hexagonal grid — how Uber finds 8 drivers in 15ms
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OAuth 2.0
Authorization Code flow, tokens, refresh — who talks to whom and exactly what they say
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Database query
SQL parser → query planner → optimizer → index scan → buffer pool → disk I/O
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MacBook boot
Power button → firmware → bootloader → kernel → launchd — every millisecond explained
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Docker
Images, layers, containers, builds — namespaces and cgroups without the hand-waving
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Uber ETA
Road graphs, A* pathfinding, Contraction Hierarchies, real-time probe data and ML — the full ETA stack
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MediaPipe × TouchDesigner
Hand detection step by step — 21 landmarks, the two-model pipeline, plugin and Python/OSC setups, pinch math driving live visuals
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How Nginx works
Event-driven architecture, reverse proxy, load balancing, SSL termination — how Nginx handles millions of requests with 4 worker processes
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How CDN works
Edge nodes, PoPs, anycast routing, cache-control headers — how a CDN turns a 150ms request into an 8ms one
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google.com — deep dive
Every hop from DNS root servers to Google's load balancer — packet inspector, resource waterfall, 16-step cheat sheet
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ZAP!
Base64 encoder
Encode text or binary data to Base64 format
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Base64 decoder
Decode Base64 strings back to plain text
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Base62 encoder
Encode numbers to compact Base62 alphanumeric strings
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Base62 decoder
Decode Base62 strings back to their numeric value
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Base58 encoder
Bitcoin/IPFS standard Base58 encoding — no ambiguous chars
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Base58 decoder
Decode Base58 encoded strings back to plain text
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URL encoder
Percent-encode URLs and query parameters safely
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URL decoder
Decode percent-encoded URLs back to readable form
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JWT decoder
Decode and inspect JWT tokens — header, payload, claims
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JSON beautifier
Format and pretty-print JSON with syntax highlighting
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JSON minifier
Compress JSON by stripping all whitespace instantly
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CSV to JSON
Convert CSV spreadsheet data to JSON instantly
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YAML ⇄ JSON
Bidirectional conversion between YAML and JSON
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XML formatter
Format and indent XML documents for readability
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PHP ⇄ JSON
Convert between JSON data and PHP array syntax
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String transformer
camelCase, snake_case, UPPER, kebab-case and more
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Clickjacking checker
Test if a site is vulnerable to clickjacking attacks
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HTTP headers
Inspect HTTP response headers for security misconfigs
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OWASP Top 10
Interactive reference for OWASP Top 10 web vulnerabilities
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Hash generator
Generate MD5, SHA-1, SHA-256, SHA-512 hashes instantly
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Caesar cipher
Encrypt and decrypt with the classic Caesar shift cipher
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Email header analyzer
Parse email headers for forensics and phishing detection
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Password generator
Generate strong random passwords with custom rules
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UUID / GUID generator
Generate RFC 4122 v4 UUIDs and GUIDs in bulk
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QR generator
Generate QR codes from any URL, text or WiFi data
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Barcode generator
Generate 1D barcodes — Code128, EAN, ISBN and more
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Lorem Ipsum
Generate dummy placeholder text for layouts and mockups
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Emoji picker
Search and copy any emoji — by name, category or keyword
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GitHub contributors
Visualize contributors for any GitHub repository
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Env generator
Generate .env file templates for various project types
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cURL describer
Paste a cURL command and get a plain-English explanation
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Cron describer
Translate cron expressions into human-readable schedules
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Regex tester
Test and debug regular expressions with live highlighting
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SQL formatter
Format and beautify SQL queries for readability
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Markdown editor
Write Markdown with live preview side by side
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Diff checker
Compare two texts and highlight differences line by line
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Mermaid renderer
Render Mermaid diagrams — flowcharts, sequence, ERD
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Docker guide
Comprehensive Docker commands reference and cheat sheet
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HTML viewer
Paste HTML and preview it rendered live in the browser
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API response tester
Test and inspect API responses and payment webhooks
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NFC reader
Read NFC tags directly in the browser via Web NFC API
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Text sharer
Share text snippets via a shareable link instantly
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Epoch converter
Convert Unix timestamps to human-readable dates and back
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Timezone converter
Convert times between any world timezones instantly
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Bash zero to hero
Complete Bash scripting reference from beginner to pro
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Network protocols
Overview of common network protocols and use cases
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HTTP protocol
Complete HTTP reference — methods, status codes, headers
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TCP protocol
TCP internals — handshake, flow control, reliability
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UDP protocol
UDP — connectionless, fast, datagram-based communication
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OSI model
Interactive OSI 7-layer model reference with examples
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DNS resolver
Full visual flow: how echobash.com resolves from root → TLD → authoritative NS → IP
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dig
Live DNS lookups — query A, MX, NS, TXT and more via Cloudflare DoH
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nslookup
Classic DNS query tool available built-in on Windows, macOS and Linux
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traceroute
Map every network hop to a destination — debug routing and latency
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Requests library
Python requests — HTTP GET, POST, headers, authentication
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Flask guide
Flask web framework — routes, templates, API patterns
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Pandas guide
Pandas DataFrames — read, filter, group, transform data
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OpenAI library
Python OpenAI SDK — chat completions, prompts, API patterns
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urllib
Python's built-in urllib for URL handling and HTTP requests
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