Developer tools
made with love.

44+ free browser-based tools for JSON formatting, security, code utilities, content processing, and AI SEO prompts.
Format JSON, decode JWTs, generate passwords, test regex, write SEO prompts, and more. Fast, private, no signup required.

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44 Developer tools
5K+ Monthly users
1M+ Tool operations
99.9% Uptime SLA

What is TOOlover?

What can I do here?

Use free browser tools for JSON formatting, validation, conversion, JWT decoding, password generation, regex testing, content counting, and AI SEO prompt creation.

Do I need an account?

No. Public tools are built for immediate use without signup, API keys, or a paid plan.

Where is my data processed?

Tools run in your browser wherever possible, so pasted JSON, secrets, and text stay on your device instead of being uploaded for processing.

JSON Formatter
Pretty-print and format JSON with configurable indentation
JSON Validator
Validate JSON syntax and structure with detailed error messages
Webhook Sender
Free online webhook sender tool to test HTTP endpoints. Send POST, GET, PUT, PATCH, and DELETE requests with custom JSON payloads, headers, and timeout options.
Payload Generator
Generate realistic webhook payloads for Stripe, GitHub, and Shopify
Webhook Receiver
Create temporary URLs to capture and inspect incoming webhooks
JWT Decoder
Decode and inspect JWT tokens — header, payload, claims, and expiry status
Secret Key Generator
Generate secure random secrets for SESSION_SECRET, JWT_SECRET, AUTH_SECRET, HMAC, API tokens, and webhooks
Password Generator
Generate cryptographically secure passwords with entropy calculation
Markdown Viewer
Convert markdown to HTML with real-time preview
Words Counter
Count words, characters, sentences, and analyze text statistics
SEO Content Brief Prompt Generator
Create a detailed AI prompt for SEO content briefs with intent, audience, outline, entities, and SERP guidance.
Blog Outline Prompt Generator
Generate a structured AI prompt for SEO-friendly blog outlines built around a keyword and audience.
Search Intent Analysis Prompt Generator
Build a prompt that asks AI to classify search intent, audience needs, SERP expectations, and content angle.

Browse by category

Explore our complete collection of developer tools organized by function. Each tool is optimized for speed and privacy — all processing happens in your browser.

JSON TOOLS

JSON Formatter
Pretty-print and format JSON with configurable indentation
JSON Validator
Validate JSON syntax and structure with detailed error messages
JSON Diff
Compare two JSON objects and highlight differences
JSON to YAML
Convert JSON to YAML format
YAML to JSON
Convert YAML to JSON format
JSON Minifier
Remove all whitespace from JSON to minimize file size
JSON Path Extractor
Extract values from JSON using dot notation paths
JSON Tree Viewer
Visualize JSON structure as an expandable tree
CSV to JSON
Convert CSV data to JSON array format
JSON to CSV
Convert JSON array to CSV format
 View all json tools →

DEVELOPER TOOLS

Regex Tester
Test regex patterns with live matching and capture groups
Cron Expression Parser
Explain cron expressions in plain English and preview the next 10 run times
UUID Generator
Generate v1/v4 UUIDs, validate UUIDs, bulk generation
URL Encoder/Decoder
Encode and decode URLs and query strings
Base64 Encoder/Decoder
Encode and decode Base64 and Base64URL
Duplicate Line Remover
Remove duplicate lines from text while preserving order
Webhook Sender
Free online webhook sender tool to test HTTP endpoints. Send POST, GET, PUT, PATCH, and DELETE requests with custom JSON payloads, headers, and timeout options.
Payload Generator
Generate realistic webhook payloads for Stripe, GitHub, and Shopify
Webhook Receiver
Create temporary URLs to capture and inspect incoming webhooks
 View all developer tools →

SECURITY TOOLS

JWT Decoder
Decode and inspect JWT tokens — header, payload, claims, and expiry status
Hash Generator
Generate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes
HMAC Generator
Generate and verify HMAC signatures for webhook verification
Secret Key Generator
Generate secure random secrets for SESSION_SECRET, JWT_SECRET, AUTH_SECRET, HMAC, API tokens, and webhooks
Bcrypt Playground
Hash passwords with bcrypt and verify hashes — adjust cost factor in the browser
Certificate Inspector
Parse and inspect X.509 certificates — view subject, issuer, expiry, SANs, fingerprint
Password Generator
Generate cryptographically secure passwords with entropy calculation
 View all security tools →

CONTENT TOOLS

Markdown Viewer
Convert markdown to HTML with real-time preview
Words Counter
Count words, characters, sentences, and analyze text statistics
 View all content tools →

AI SEO PROMPT TOOLS

SEO Content Brief Prompt Generator
Create a detailed AI prompt for SEO content briefs with intent, audience, outline, entities, and SERP guidance.
Blog Outline Prompt Generator
Generate a structured AI prompt for SEO-friendly blog outlines built around a keyword and audience.
Search Intent Analysis Prompt Generator
Build a prompt that asks AI to classify search intent, audience needs, SERP expectations, and content angle.
Keyword Cluster Prompt Generator
Create a prompt for grouping keyword lists into SEO clusters, pillar pages, supporting pages, and intent groups.
Meta Title & Description Prompt Generator
Generate a prompt for writing SEO meta titles and descriptions with variants, intent fit, and character discipline.
Content Refresh Prompt Generator
Create a prompt for refreshing old blog posts with new intent coverage, stronger sections, and SEO improvements.
FAQ & People Also Ask Prompt Generator
Generate a prompt for finding FAQ and People Also Ask style questions for SEO articles.
 View all ai seo prompt tools →

UTILITY TOOLS

Time Converter
Convert between different time units
Size Converter
Convert between different file size units
Temperature Converter
Convert between Celsius, Fahrenheit, and Kelvin
 View all utility tools →