Developer tools
made with love.

40+ 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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40 Developer tools

5K+ Monthly users

1M+ Tool operations

99.9% Uptime SLA

Featured tools

Pretty-print and format JSON with configurable indentation

Validate JSON syntax and structure with detailed error messages

Decode and inspect JWT tokens — header, payload, claims, and expiry status

Password Generator

Generate cryptographically secure passwords with entropy calculation

Markdown Viewer

Convert markdown to HTML with real-time preview

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

Pretty-print and format JSON with configurable indentation

Validate JSON syntax and structure with detailed error messages

Compare two JSON objects and highlight differences

Convert JSON to YAML format

Convert YAML to JSON format

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DEVELOPER TOOLS

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

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

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SECURITY TOOLS

Decode and inspect JWT tokens — header, payload, claims, and expiry status

Generate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes

Generate and verify HMAC signatures for webhook verification

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

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CONTENT TOOLS

Markdown Viewer

Convert markdown to HTML with real-time preview

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.

View all ai seo prompt tools →

UTILITY TOOLS

Convert between different time units

Convert between different file size units

Temperature Converter

Convert between Celsius, Fahrenheit, and Kelvin

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