Private developer tools with zero server uploads.

Check your resume ATS compatibility and keyword score

GitHub README Generator

Generate professional GitHub README.md files

Hash Generator

Generate SHA-256, SHA-512, MD5, CRC32, and HMAC digests

Diff Checker

Compare code and text with unified diff patch generation

Cron Parser

Parse cron expressions, humanize schedules, and project runs

YAML ↔ JSON Converter

Convert between YAML and JSON documents in real time

Unit Converter

Convert data storage sizes and CSS typography units

Markdown Previewer

Live GitHub Flavored Markdown editor and HTML compiler

Mock Data Generator

Generate technical placeholder text and user fixtures

Token Generator

Generate API tokens, NanoIDs and calculate password entropy

AI Text Humanizer

Humanize AI text into natural writing — private, on-device

Paraphraser

Rephrase sentences and paragraphs in multiple tones

AI RAG Assistant

Ask DevToolkit Hub docs with local or Hugging Face RAG

Document RAG

Chat with your notes using a RAG pipeline

AI Summarizer

Summarize long text with Hugging Face BART

AI Sentiment Analyzer

Sentiment and zero-shot themes with HF models

Semantic Similarity

Compare meaning with MiniLM embeddings

JSON to TypeScript

Convert JSON to TypeScript interfaces and type definitions

cURL to Code Converter

Convert cURL commands to JavaScript Fetch, Axios, Python & Go

JSON to Zod Schema

Convert JSON payloads into Zod validation schemas and TypeScript types

SVG to JSX Converter

Convert SVG code into clean React (JSX/TSX) components

Chmod Permissions Calculator

Calculate Unix file permissions, octal numbers & symbolic notation

CSV ↔ JSON Converter

Convert between CSV and JSON with delimiter controls and auto-flattening

JSON Repair & Fixer

Repair malformed JSON, unquoted keys, Python dicts, and trailing commas

JSON to CSV Converter

Convert JSON arrays and nested objects to RFC 4180 CSV tables

CSV to JSON Converter

Convert CSV spreadsheets and tabular data into JSON arrays

JSON to YAML Converter

Convert JSON objects and arrays into clean indented YAML

YAML to JSON Converter

Convert YAML manifests and config files into structured JSON

Subnet Calculator & CIDR

Calculate IPv4 subnets, CIDR masks, network & broadcast IPs, and usable host ranges

Slug Generator & URL Slugify

Convert titles, articles, and product names into clean, SEO-friendly URL slugs

HTML Entity Encoder & Decoder

Encode and decode HTML entities, special characters, and numeric code points client-side

URL Parser & Query Inspector

Parse RFC 3986 URLs, inspect components, and edit query strings & UTM parameters

SemVer Calculator & Range Checker

Test package version ranges (^, ~, >=, ||), preview version bumps, and compare precedence

HTML to Markdown Converter

Convert HTML markup into clean Markdown with table support and token reduction for LLMs

Docker Run to Compose Converter

Convert docker run commands into clean docker-compose.yml specifications

Password & Passphrase Generator

Generate secure passwords and Diceware passphrases with NIST SP 800-63B entropy metrics

Meta Tag & Social Preview Generator

Generate SEO meta tags, Open Graph cards, and Next.js metadata with live search & social previews

User-Agent & Client Hints Parser

Parse User-Agent strings, detect browser, OS, engine & device, audit bot crawlers & generate Client Hints

ULID Generator & Decoder

Generate sortable 128-bit Crockford Base32 ULIDs, decode timestamps, and convert to UUIDs

Wi-Fi QR Code Generator

Generate scannable Wi-Fi login QR codes with printable guest cards and zero password uploads

TOTP 2FA Token Generator

Generate RFC 6238 time-based 2FA one-time passwords, test authenticator secrets & preview QR codes

HMAC Generator & Webhook Verifier

Compute HMAC signatures (SHA-256/512) and verify GitHub, Stripe, Slack & Shopify webhook deliveries

Number Base Converter & Programmer Calculator

Convert binary, hex, decimal, and octal with BigInt precision, interactive 32/64-bit flipper & bitwise logic

XML ↔ JSON Converter & Formatter

Convert between XML and JSON documents with attribute preservation, CDATA & namespaces

CSS Box Shadow & Glassmorphism Generator

Design multi-layer smooth box shadows and frosted glassmorphism UI with real-time CSS & Tailwind export

JSONPath Tester & Query Evaluator

Test and evaluate JSONPath expressions (RFC 9535) against JSON payloads with live node highlighting

.env Multi-Format Converter & Secrets Masker

Convert .env files into JSON, YAML, Docker Compose, Kubernetes ConfigMap & Secret, with 1-click secrets masking

.htpasswd & HTTP Basic Auth Generator

Generate Apache APR1-MD5 & SHA-1 .htpasswd hashes, verify existing lines, and build Basic Auth headers

SVG to CSS & Data URI Generator

Convert SVG vectors into CSS background-image, mask-image, Tailwind classes & Data URIs with live preview

Featured Tools

View all tools →

JSON Formatter

Beautify and format JSON with syntax highlighting

JWT Decoder

Decode and inspect JSON Web Tokens client-side

Regex Tester

Test regular expressions with live match highlighting

Word Counter

Count words, characters, sentences and reading time

QR Code Generator

Generate QR codes for URLs, text, email and more

CGPA Calculator

Calculate GPA and CGPA from grades and credit hours

Resume ATS Checker

Check your resume ATS compatibility and keyword score

Hash Generator

Generate SHA-256, SHA-512, MD5, CRC32, and HMAC digests

Diff Checker

Compare code and text with unified diff patch generation

Cron Parser

Parse cron expressions, humanize schedules, and project runs

YAML ↔ JSON Converter

Convert between YAML and JSON documents in real time

Markdown Previewer

Live GitHub Flavored Markdown editor and HTML compiler

Token Generator

Generate API tokens, NanoIDs and calculate password entropy

AI Text Humanizer

Humanize AI text into natural writing — private, on-device

Paraphraser

Rephrase sentences and paragraphs in multiple tones

AI RAG Assistant

Ask DevToolkit Hub docs with local or Hugging Face RAG

Document RAG

Chat with your notes using a RAG pipeline

AI Summarizer

Summarize long text with Hugging Face BART

AI Sentiment Analyzer

Sentiment and zero-shot themes with HF models

Semantic Similarity

Compare meaning with MiniLM embeddings

JSON to TypeScript

Convert JSON to TypeScript interfaces and type definitions

cURL to Code Converter

Convert cURL commands to JavaScript Fetch, Axios, Python & Go

JSON to Zod Schema

Convert JSON payloads into Zod validation schemas and TypeScript types

SVG to JSX Converter

Convert SVG code into clean React (JSX/TSX) components

Chmod Permissions Calculator

Calculate Unix file permissions, octal numbers & symbolic notation

CSV ↔ JSON Converter

Convert between CSV and JSON with delimiter controls and auto-flattening

JSON Repair & Fixer

Repair malformed JSON, unquoted keys, Python dicts, and trailing commas

JSON to CSV Converter

Convert JSON arrays and nested objects to RFC 4180 CSV tables

CSV to JSON Converter

Convert CSV spreadsheets and tabular data into JSON arrays

JSON to YAML Converter

Convert JSON objects and arrays into clean indented YAML

YAML to JSON Converter

Convert YAML manifests and config files into structured JSON

Subnet Calculator & CIDR

Calculate IPv4 subnets, CIDR masks, network & broadcast IPs, and usable host ranges

Slug Generator & URL Slugify

Convert titles, articles, and product names into clean, SEO-friendly URL slugs

HTML Entity Encoder & Decoder

Encode and decode HTML entities, special characters, and numeric code points client-side

URL Parser & Query Inspector

Parse RFC 3986 URLs, inspect components, and edit query strings & UTM parameters

SemVer Calculator & Range Checker

Test package version ranges (^, ~, >=, ||), preview version bumps, and compare precedence

HTML to Markdown Converter

Convert HTML markup into clean Markdown with table support and token reduction for LLMs

Docker Run to Compose Converter

Convert docker run commands into clean docker-compose.yml specifications

Password & Passphrase Generator

Generate secure passwords and Diceware passphrases with NIST SP 800-63B entropy metrics

Meta Tag & Social Preview Generator

Generate SEO meta tags, Open Graph cards, and Next.js metadata with live search & social previews

User-Agent & Client Hints Parser

Parse User-Agent strings, detect browser, OS, engine & device, audit bot crawlers & generate Client Hints

ULID Generator & Decoder

Generate sortable 128-bit Crockford Base32 ULIDs, decode timestamps, and convert to UUIDs

Wi-Fi QR Code Generator

Generate scannable Wi-Fi login QR codes with printable guest cards and zero password uploads

TOTP 2FA Token Generator

Generate RFC 6238 time-based 2FA one-time passwords, test authenticator secrets & preview QR codes

HMAC Generator & Webhook Verifier

Compute HMAC signatures (SHA-256/512) and verify GitHub, Stripe, Slack & Shopify webhook deliveries

Number Base Converter & Programmer Calculator

Convert binary, hex, decimal, and octal with BigInt precision, interactive 32/64-bit flipper & bitwise logic

XML ↔ JSON Converter & Formatter

Convert between XML and JSON documents with attribute preservation, CDATA & namespaces

CSS Box Shadow & Glassmorphism Generator

Design multi-layer smooth box shadows and frosted glassmorphism UI with real-time CSS & Tailwind export

JSONPath Tester & Query Evaluator

Test and evaluate JSONPath expressions (RFC 9535) against JSON payloads with live node highlighting

.env Multi-Format Converter & Secrets Masker

Convert .env files into JSON, YAML, Docker Compose, Kubernetes ConfigMap & Secret, with 1-click secrets masking

.htpasswd & HTTP Basic Auth Generator

Generate Apache APR1-MD5 & SHA-1 .htpasswd hashes, verify existing lines, and build Basic Auth headers

SVG to CSS & Data URI Generator

Convert SVG vectors into CSS background-image, mask-image, Tailwind classes & Data URIs with live preview

JSON FormatterJSON ValidatorJSON Minifier+47 more

Organized

Browse by Category

Developer Tools

Format, encode, decode and debug code

Text Tools

Transform and analyze any text

Word CounterCharacter CounterCase Converter+10 more

Image Tools

Generate, compress and edit images

QR Code GeneratorImage CompressorImage Resizer+2 more

Student Tools

Academic calculators and tools

CGPA CalculatorScientific CalculatorPercentage Calculator

Career Tools

Level up your professional game

Resume ATS CheckerGitHub README Generator

Quick references

Developer Cheat Sheets

All 9 cheat sheets →

Databases

SQL Commands & Queries

JOINs, window functions, CTEs, GROUP BY, upserts & indexing

Cloud / K8s

Kubernetes & Kubectl

Pods, rollouts, secrets, node draining & debugging

Containers

Docker & Compose

Containers, compose flags, multi-stage builds & prune

DevOps

Linux & Bash

File ops, chmod permissions, grep, ports & systemctl

Web APIs

HTTP Status Codes

1xx to 5xx response codes with causes & fixes

Scheduling

Cron Expressions

5-field syntax guide with 25+ schedule presets

Version Control

Git Commands

Branching, cherry-pick, undo commits & stashing

Patterns

Regex Patterns

Production regex for email, URL, passwords & UUID

Documentation

Markdown & GFM

Tables, task lists, code fences & callout alerts

Complete collection

All 73 Developer Tools

Organized view →

JSON Formatter

Beautify and format JSON with syntax highlighting

JSON Validator

Validate JSON syntax and catch errors instantly

JSON Minifier

Minify JSON by removing whitespace to reduce size

JWT Decoder

Decode and inspect JSON Web Tokens client-side

UUID Generator

Generate v4 UUIDs in bulk with one click

Base64 Encoder/Decoder

Encode and decode Base64 strings instantly

Regex Tester

Test regular expressions with live match highlighting

URL Encoder/Decoder

Encode and decode URL components and query strings

SQL Formatter

Format and beautify SQL queries for readability

HTML Formatter

Beautify and format HTML markup with indentation

CSS Formatter

Beautify and minify CSS stylesheets

Timestamp Converter

Convert Unix timestamps to human-readable dates

Word Counter

Count words, characters, sentences and reading time

Character Counter

Count chars with Twitter, SMS and platform limits

Case Converter

Convert between camelCase, snake_case, UPPER and more

Duplicate Line Remover

Remove duplicate lines from any list instantly

Text Sorter

Sort lines alphabetically, numerically or by length

QR Code Generator

Generate QR codes for URLs, text, email and more

Image Compressor

Compress images client-side without quality loss

Image Resizer

Resize images to exact dimensions or percentages

Color Picker

Pick colors and convert between HEX, RGB and HSL

CGPA Calculator

Calculate GPA and CGPA from grades and credit hours

Scientific Calculator

Full-featured scientific calculator with history

Percentage Calculator

Calculate percentages, discounts and changes

Resume ATS Checker

Check your resume ATS compatibility and keyword score

GitHub README Generator

Generate professional GitHub README.md files

Hash Generator

Generate SHA-256, SHA-512, MD5, CRC32, and HMAC digests

Diff Checker

Compare code and text with unified diff patch generation

Cron Parser

Parse cron expressions, humanize schedules, and project runs

YAML ↔ JSON Converter

Convert between YAML and JSON documents in real time

Unit Converter

Convert data storage sizes and CSS typography units

Markdown Previewer

Live GitHub Flavored Markdown editor and HTML compiler

Mock Data Generator

Generate technical placeholder text and user fixtures

Token Generator

Generate API tokens, NanoIDs and calculate password entropy

AI Text Humanizer

Humanize AI text into natural writing — private, on-device

Paraphraser

Rephrase sentences and paragraphs in multiple tones

AI RAG Assistant

Ask DevToolkit Hub docs with local or Hugging Face RAG

Document RAG

Chat with your notes using a RAG pipeline

AI Summarizer

Summarize long text with Hugging Face BART

AI Sentiment Analyzer

Sentiment and zero-shot themes with HF models

Semantic Similarity

Compare meaning with MiniLM embeddings

JSON to TypeScript

Convert JSON to TypeScript interfaces and type definitions

cURL to Code Converter

Convert cURL commands to JavaScript Fetch, Axios, Python & Go

JSON to Zod Schema

Convert JSON payloads into Zod validation schemas and TypeScript types

SVG to JSX Converter

Convert SVG code into clean React (JSX/TSX) components

Chmod Permissions Calculator

Calculate Unix file permissions, octal numbers & symbolic notation

CSV ↔ JSON Converter

Convert between CSV and JSON with delimiter controls and auto-flattening

JSON Repair & Fixer

Repair malformed JSON, unquoted keys, Python dicts, and trailing commas

JSON to CSV Converter

Convert JSON arrays and nested objects to RFC 4180 CSV tables

CSV to JSON Converter

Convert CSV spreadsheets and tabular data into JSON arrays

JSON to YAML Converter

Convert JSON objects and arrays into clean indented YAML

YAML to JSON Converter

Convert YAML manifests and config files into structured JSON

Subnet Calculator & CIDR

Calculate IPv4 subnets, CIDR masks, network & broadcast IPs, and usable host ranges

Slug Generator & URL Slugify

Convert titles, articles, and product names into clean, SEO-friendly URL slugs

HTML Entity Encoder & Decoder

Encode and decode HTML entities, special characters, and numeric code points client-side

URL Parser & Query Inspector

Parse RFC 3986 URLs, inspect components, and edit query strings & UTM parameters

SemVer Calculator & Range Checker

Test package version ranges (^, ~, >=, ||), preview version bumps, and compare precedence

HTML to Markdown Converter

Convert HTML markup into clean Markdown with table support and token reduction for LLMs

Docker Run to Compose Converter

Convert docker run commands into clean docker-compose.yml specifications

Password & Passphrase Generator

Generate secure passwords and Diceware passphrases with NIST SP 800-63B entropy metrics

Meta Tag & Social Preview Generator

Generate SEO meta tags, Open Graph cards, and Next.js metadata with live search & social previews

User-Agent & Client Hints Parser

Parse User-Agent strings, detect browser, OS, engine & device, audit bot crawlers & generate Client Hints

ULID Generator & Decoder

Generate sortable 128-bit Crockford Base32 ULIDs, decode timestamps, and convert to UUIDs

Wi-Fi QR Code Generator

Generate scannable Wi-Fi login QR codes with printable guest cards and zero password uploads

TOTP 2FA Token Generator

Generate RFC 6238 time-based 2FA one-time passwords, test authenticator secrets & preview QR codes

HMAC Generator & Webhook Verifier

Compute HMAC signatures (SHA-256/512) and verify GitHub, Stripe, Slack & Shopify webhook deliveries

Number Base Converter & Programmer Calculator

Convert binary, hex, decimal, and octal with BigInt precision, interactive 32/64-bit flipper & bitwise logic

XML ↔ JSON Converter & Formatter

Convert between XML and JSON documents with attribute preservation, CDATA & namespaces

CSS Box Shadow & Glassmorphism Generator

Design multi-layer smooth box shadows and frosted glassmorphism UI with real-time CSS & Tailwind export

JSONPath Tester & Query Evaluator

Test and evaluate JSONPath expressions (RFC 9535) against JSON payloads with live node highlighting

.env Multi-Format Converter & Secrets Masker

Convert .env files into JSON, YAML, Docker Compose, Kubernetes ConfigMap & Secret, with 1-click secrets masking

.htpasswd & HTTP Basic Auth Generator

Generate Apache APR1-MD5 & SHA-1 .htpasswd hashes, verify existing lines, and build Basic Auth headers

SVG to CSS & Data URI Generator

Convert SVG vectors into CSS background-image, mask-image, Tailwind classes & Data URIs with live preview