# LangStop — Free Developer Tools

> 180+ free, privacy-first developer tools. 100% browser-based. No signup, no server uploads.

## JSON Tools

50+ browser-based tools for formatting, validating, converting, diffing, querying, transforming, and generating code from JSON. All client-side — no uploads.

- JSON Formatter: https://langstop.com/json-formatter
- JSON Validator: https://langstop.com/json-validator
- JSON Minifier: https://langstop.com/json-minifier
- JSON Diff: https://langstop.com/json-diff
- JSON Path Query: https://langstop.com/json-path-query
- JSON Sorter: https://langstop.com/json-sorter
- JSON Flatten: https://langstop.com/json-flatten
- Fix JSON: https://langstop.com/fix-json
- JSON Escape/Unescape: https://langstop.com/json-escape-unescape
- JSON to YAML: https://langstop.com/json-to-yaml
- JSON to XML: https://langstop.com/json-to-xml
- JSON to CSV: https://langstop.com/json-to-csv
- JSON to TSV: https://langstop.com/json-to-tsv
- JSON to TOML: https://langstop.com/json-to-toml
- JSON to INI: https://langstop.com/json-to-ini
- JSON to ENV: https://langstop.com/json-to-env
- JSON to Java Properties: https://langstop.com/json-to-java-properties
- JSON to PHP Array: https://langstop.com/json-to-php-array
- JSON to PHP INI: https://langstop.com/json-to-php-ini
- JSON to Python Dict: https://langstop.com/json-to-python-dict
- JSON to String: https://langstop.com/json-to-string
- JSON to JSON Schema: https://langstop.com/json-to-json-schema
- JSON to Code: https://langstop.com/json-to-code
- JSON Mock Data Generator: https://langstop.com/json-mock-data-generator
- JSON Schema GUI Builder: https://langstop.com/json-schema-gui-builder
- JSON Transform: https://langstop.com/json-transform
- JSON URL Encoder: https://langstop.com/json-url-encoder
- JSON URL Decoder: https://langstop.com/json-url-decoder
- CSV to JSON: https://langstop.com/csv-to-json
- YAML to JSON: https://langstop.com/yaml-to-json
- XML to JSON: https://langstop.com/xml-to-json
- TOML to JSON: https://langstop.com/toml-to-json
- String to JSON: https://langstop.com/string-to-json
- PHP Array to JSON: https://langstop.com/php-array-to-json
- PHP INI to JSON: https://langstop.com/php-ini-to-json
- Python Dict to JSON: https://langstop.com/python-dict-to-json
- ENV to JSON: https://langstop.com/env-to-json
- INI to JSON: https://langstop.com/ini-to-json
- Java Properties to JSON: https://langstop.com/java-properties-to-json
- Bash Properties to JSON: https://langstop.com/bash-properties-to-json

## YAML Tools

25+ tools for formatting, validating, converting, and generating code from YAML. Client-side only.

- YAML Formatter: https://langstop.com/yaml-formatter
- YAML Validator: https://langstop.com/yaml-validator
- YAML to JSON: https://langstop.com/yaml-to-json
- YAML to XML: https://langstop.com/yaml-to-xml
- YAML to CSV: https://langstop.com/yaml-to-csv
- YAML to TOML: https://langstop.com/yaml-to-toml
- YAML to INI: https://langstop.com/yaml-to-ini
- YAML to ENV: https://langstop.com/yaml-to-env
- YAML to Java Properties: https://langstop.com/yaml-to-java-properties
- YAML to PHP Array: https://langstop.com/yaml-to-php-array
- YAML to PHP INI: https://langstop.com/yaml-to-php-ini
- YAML to Python Dict: https://langstop.com/yaml-to-python-dict
- YAML to JSON Schema: https://langstop.com/yaml-to-json-schema
- YAML to Code: https://langstop.com/yaml-to-code
- YAML URL Encoder: https://langstop.com/yaml-url-encoder
- YAML URL Decoder: https://langstop.com/yaml-url-decoder
- CSV to YAML: https://langstop.com/csv-to-yaml
- TOML to YAML: https://langstop.com/toml-to-yaml
- XML to YAML: https://langstop.com/xml-to-yaml
- ENV to YAML: https://langstop.com/env-to-yaml
- INI to YAML: https://langstop.com/ini-to-yaml
- Java Properties to YAML: https://langstop.com/java-properties-to-yaml
- PHP Array to YAML: https://langstop.com/php-array-to-yaml
- PHP INI to YAML: https://langstop.com/php-ini-to-yaml
- Python Dict to YAML: https://langstop.com/python-dict-to-yaml
- Bash Properties to YAML: https://langstop.com/bash-properties-to-yaml

## XML Tools

15+ tools for formatting, validating, converting, and generating code from XML. All in-browser.

- XML Formatter: https://langstop.com/xml-formatter
- XML Validator: https://langstop.com/xml-validator
- XML Minifier: https://langstop.com/xml-minifier
- XML to JSON: https://langstop.com/xml-to-json
- XML to YAML: https://langstop.com/xml-to-yaml
- XML to CSV: https://langstop.com/xml-to-csv
- XML to TOML: https://langstop.com/xml-to-toml
- XML to JSON Schema: https://langstop.com/xml-to-json-schema
- XML to Code: https://langstop.com/xml-to-code
- XML Mock Data Generator: https://langstop.com/xml-mock-data-generator
- XML URL Encoder: https://langstop.com/xml-url-encoder
- XML URL Decoder: https://langstop.com/xml-url-decoder
- JSON to XML: https://langstop.com/json-to-xml
- CSV to XML: https://langstop.com/csv-to-xml
- YAML to XML: https://langstop.com/yaml-to-xml
- TOML to XML: https://langstop.com/toml-to-xml

## Code Generators — JSON to Language

Convert JSON data structures into strongly-typed code for 20+ languages: TypeScript, Go, Rust, Python, Java, C++, C#, Kotlin, Swift, and more.

- JSON to TypeScript: https://langstop.com/json-to-typescript
- JSON to TypeScript (Zod): https://langstop.com/json-to-typescript-zod
- JSON to TypeScript (Effect Schema): https://langstop.com/json-to-typescript-effect-schema
- JSON to JavaScript: https://langstop.com/json-to-javascript
- JSON to JavaScript PropTypes: https://langstop.com/json-to-javascript-prop-types
- JSON to Python: https://langstop.com/json-to-python
- JSON to Go: https://langstop.com/json-to-go
- JSON to Rust: https://langstop.com/json-to-rust
- JSON to Java: https://langstop.com/json-to-java
- JSON to Kotlin: https://langstop.com/json-to-kotlin
- JSON to Swift: https://langstop.com/json-to-swift
- JSON to C++: https://langstop.com/json-to-cpp
- JSON to C#: https://langstop.com/json-to-csharp
- JSON to Dart: https://langstop.com/json-to-dart
- JSON to PHP: https://langstop.com/json-to-php
- JSON to Ruby: https://langstop.com/json-to-ruby
- JSON to Scala: https://langstop.com/json-to-scala
- JSON to Haskell: https://langstop.com/json-to-haskell
- JSON to Elm: https://langstop.com/json-to-elm
- JSON to Flow: https://langstop.com/json-to-flow
- JSON to Pike: https://langstop.com/json-to-pike
- JSON to Objective-C: https://langstop.com/json-to-objective-c
- JSON to Bash: https://langstop.com/json-to-bash

## Code Generators — XML to Language

Convert XML schemas into strongly-typed code for 20+ languages. All browser-based.

- XML to TypeScript: https://langstop.com/xml-to-typescript
- XML to TypeScript (Zod): https://langstop.com/xml-to-typescript-zod
- XML to TypeScript (Effect Schema): https://langstop.com/xml-to-typescript-effect-schema
- XML to JavaScript: https://langstop.com/xml-to-javascript
- XML to JavaScript PropTypes: https://langstop.com/xml-to-javascript-prop-types
- XML to Python: https://langstop.com/xml-to-python
- XML to Go: https://langstop.com/xml-to-go
- XML to Rust: https://langstop.com/xml-to-rust
- XML to Java: https://langstop.com/xml-to-java
- XML to Kotlin: https://langstop.com/xml-to-kotlin
- XML to Swift: https://langstop.com/xml-to-swift
- XML to C++: https://langstop.com/xml-to-cpp
- XML to C#: https://langstop.com/xml-to-csharp
- XML to Dart: https://langstop.com/xml-to-dart
- XML to PHP: https://langstop.com/xml-to-php
- XML to Ruby: https://langstop.com/xml-to-ruby
- XML to Scala: https://langstop.com/xml-to-scala
- XML to Haskell: https://langstop.com/xml-to-haskell
- XML to Elm: https://langstop.com/xml-to-elm
- XML to Flow: https://langstop.com/xml-to-flow
- XML to Pike: https://langstop.com/xml-to-pike
- XML to Objective-C: https://langstop.com/xml-to-objective-c

## Code Generators — YAML to Language

Convert YAML configs into strongly-typed code for 22+ languages. Client-side only — no uploads.

- YAML to TypeScript: https://langstop.com/yaml-to-typescript
- YAML to TypeScript (Zod): https://langstop.com/yaml-to-typescript-zod
- YAML to TypeScript (Effect Schema): https://langstop.com/yaml-to-typescript-effect-schema
- YAML to JavaScript: https://langstop.com/yaml-to-javascript
- YAML to JavaScript PropTypes: https://langstop.com/yaml-to-javascript-prop-types
- YAML to Python: https://langstop.com/yaml-to-python
- YAML to Go: https://langstop.com/yaml-to-go
- YAML to Rust: https://langstop.com/yaml-to-rust
- YAML to Java: https://langstop.com/yaml-to-java
- YAML to Kotlin: https://langstop.com/yaml-to-kotlin
- YAML to Swift: https://langstop.com/yaml-to-swift
- YAML to C++: https://langstop.com/yaml-to-cpp
- YAML to C#: https://langstop.com/yaml-to-csharp
- YAML to Dart: https://langstop.com/yaml-to-dart
- YAML to PHP: https://langstop.com/yaml-to-php
- YAML to Ruby: https://langstop.com/yaml-to-ruby
- YAML to Scala: https://langstop.com/yaml-to-scala
- YAML to Haskell: https://langstop.com/yaml-to-haskell
- YAML to Elm: https://langstop.com/yaml-to-elm
- YAML to Flow: https://langstop.com/yaml-to-flow
- YAML to Pike: https://langstop.com/yaml-to-pike
- YAML to Objective-C: https://langstop.com/yaml-to-objective-c
- YAML to Bash: https://langstop.com/yaml-to-bash

## Encoding & Decoding Tools

Base64, URL, and hash encoding/decoding tools. All processing stays in your browser.

- Base64 Encoder: https://langstop.com/base64-encoder
- Base64 Decoder: https://langstop.com/base64-decoder
- Base64 Converter: https://langstop.com/base64-converter
- Base64 to Image: https://langstop.com/base64-to-image
- URL Encoder: https://langstop.com/url-encoder
- URL Decoder: https://langstop.com/url-decoder
- JSON URL Encoder: https://langstop.com/json-url-encoder
- JSON URL Decoder: https://langstop.com/json-url-decoder
- XML URL Encoder: https://langstop.com/xml-url-encoder
- XML URL Decoder: https://langstop.com/xml-url-decoder
- YAML URL Encoder: https://langstop.com/yaml-url-encoder
- YAML URL Decoder: https://langstop.com/yaml-url-decoder
- Hash Generator: https://langstop.com/hash-generator

## Security & Token Tools

JWT encode/decode, hash generation, and password utilities. 100% client-side.

- JWT Encoder: https://langstop.com/jwt-encoder
- JWT Decoder: https://langstop.com/jwt-decoder
- Hash Generator: https://langstop.com/hash-generator
- Password Generator: https://langstop.com/password-generator

## UUID & ID Generators

Generate UUIDs v1–v7, GUIDs, and ULIDs. Fully client-side with cryptographically secure randomness.

- UUID Generator: https://langstop.com/uuid-generator
- UUID v1 Generator: https://langstop.com/uuid-generator/v1
- UUID v3 Generator: https://langstop.com/uuid-generator/v3
- UUID v4 Generator: https://langstop.com/uuid-generator/v4
- UUID v5 Generator: https://langstop.com/uuid-generator/v5
- UUID v7 Generator: https://langstop.com/uuid-generator/v7
- GUID Generator: https://langstop.com/uuid-generator/guid
- ULID Generator: https://langstop.com/uuid-generator/ulid

## Time & Date Tools

Epoch timestamps, cron scheduling, and age calculation tools. All browser-based.

- Epoch Timestamp Converter: https://langstop.com/epoch-timestamp-converter
- Age Calculator: https://langstop.com/age-calculator
- Cron Helper: https://langstop.com/cron-helper

## API & HTTP Tools

REST client, WebSocket tester, and OpenAPI editor. No server proxying — requests go direct.

- REST API Client: https://langstop.com/rest-api-client
- WebSocket Client: https://langstop.com/websocket-client
- OpenAPI Editor: https://langstop.com/openapi-editor

## Text & String Tools

Regex testing, text diff, counters, case converters, code formatters, and Markdown editing.

- Regex Tester: https://langstop.com/regex-tester
- Text Diff Checker: https://langstop.com/text-diff
- Word Counter: https://langstop.com/text-utils/word-counter
- Character Counter: https://langstop.com/text-utils/character-counter
- Line Counter: https://langstop.com/text-utils/line-counter
- Duplicate Counter: https://langstop.com/text-utils/duplicate-counter
- String Case Converter: https://langstop.com/text-utils/string-case-converter
- Sort Lines: https://langstop.com/text-utils/sort-lines
- Sort Words: https://langstop.com/text-utils/sort-words
- Remove Duplicates: https://langstop.com/text-utils/remove-duplicates
- Spaces to Newlines: https://langstop.com/text-utils/spaces-to-newlines
- LLM Token Counter: https://langstop.com/text-utils/llm-token-counter
- HTML Formatter: https://langstop.com/html-formatter
- SQL Formatter: https://langstop.com/sql-formatter
- JavaScript Minifier: https://langstop.com/javascript-minifier
- JavaScript Formatter: https://langstop.com/formatters/javascript-formatter
- TypeScript Formatter: https://langstop.com/formatters/typescript-formatter
- Java Formatter: https://langstop.com/formatters/java-formatter
- Elm Formatter: https://langstop.com/formatters/elm-formatter
- Markdown Editor: https://langstop.com/markdown-editor

## CSS & Preprocessor Tools

CSS formatting, validation, minification, specificity, variables, and preprocessor conversion (SCSS/Less/Stylus). Includes color workbench and color converter.

- Color Workbench: https://langstop.com/color-workbench
- CSS Formatter: https://langstop.com/css-formatter
- CSS Pretty Print: https://langstop.com/css-pretty-print
- CSS Minifier: https://langstop.com/css-minifier
- CSS Validator: https://langstop.com/css-validator
- CSS Diff: https://langstop.com/css-diff
- CSS Specificity: https://langstop.com/css-specificity
- CSS Variables: https://langstop.com/css-variables
- CSS Colors: https://langstop.com/css-colors
- CSS Selector Tester: https://langstop.com/css-selector-tester
- CSS to SCSS: https://langstop.com/css-to-scss
- CSS to LESS: https://langstop.com/css-to-less
- CSS to SASS: https://langstop.com/css-to-sass
- CSS to Stylus: https://langstop.com/css-to-stylus
- SCSS to CSS: https://langstop.com/scss-to-css
- SCSS to LESS: https://langstop.com/scss-to-less
- SCSS to SASS: https://langstop.com/scss-to-sass
- SCSS to Stylus: https://langstop.com/scss-to-stylus
- SASS to CSS: https://langstop.com/sass-to-css
- SASS to LESS: https://langstop.com/sass-to-less
- SASS to SCSS: https://langstop.com/sass-to-scss
- SASS to Stylus: https://langstop.com/sass-to-stylus
- LESS to CSS: https://langstop.com/less-to-css
- LESS to SCSS: https://langstop.com/less-to-scss
- LESS to SASS: https://langstop.com/less-to-sass
- LESS to Stylus: https://langstop.com/less-to-stylus
- Stylus to CSS: https://langstop.com/stylus-to-css
- Stylus to LESS: https://langstop.com/stylus-to-less
- Stylus to SCSS: https://langstop.com/stylus-to-scss
- Stylus to SASS: https://langstop.com/stylus-to-sass
- LESS Formatter: https://langstop.com/less-formatter
- SCSS Formatter: https://langstop.com/scss-formatter

## Data Conversion Tools

Convert between CSV, JSON, YAML, XML, TOML, and SQL. All transformations are client-side.

- CSV to JSON: https://langstop.com/csv-to-json
- CSV to YAML: https://langstop.com/csv-to-yaml
- CSV to XML: https://langstop.com/csv-to-xml
- JSON to CSV: https://langstop.com/json-to-csv
- JSON to TSV: https://langstop.com/json-to-tsv
- SQL Formatter: https://langstop.com/sql-formatter
- CSV Mock Data Generator: https://langstop.com/csv-mock-data-generator

## TOML Tools

Convert TOML configs to JSON, YAML, and XML. All in-browser.

- TOML to JSON: https://langstop.com/toml-to-json
- TOML to YAML: https://langstop.com/toml-to-yaml
- TOML to XML: https://langstop.com/toml-to-xml

## Database & ERD Tools

Entity-relationship diagram generator, SQL formatter, and schema visualization. Interactive, client-side.

- ERD Generator: https://langstop.com/erd-generator
- ERD Generator (Editor): https://langstop.com/erd-generator/editor
- ERD Generator (Workspaces): https://langstop.com/erd-generator/workspaces
- SchemaCode ERD Generator: https://langstop.com/schemacode/erd-generator

## Linux & DevOps Tools

Interactive command builders for 25+ Linux/CLI tools: grep, sed, awk, find, curl, ssh, nmap, tar, cron, and more.

- Linux Command Builders: https://langstop.com/linux-tools
- awk Command Builder: https://langstop.com/linux-tools/awk-command-builder
- chmod Command Builder: https://langstop.com/linux-tools/chmod-command-builder
- cp Command Builder: https://langstop.com/linux-tools/cp-command-builder
- crontab Command Builder: https://langstop.com/linux-tools/crontab-command-builder
- curl Command Builder: https://langstop.com/linux-tools/curl-command-builder
- cut Command Builder: https://langstop.com/linux-tools/cut-command-builder
- df Command Builder: https://langstop.com/linux-tools/df-command-builder
- du Command Builder: https://langstop.com/linux-tools/du-command-builder
- file Command Builder: https://langstop.com/linux-tools/file-command-builder
- find Command Builder: https://langstop.com/linux-tools/find-command-builder
- grep Command Builder: https://langstop.com/linux-tools/grep-command-builder
- kill Command Builder: https://langstop.com/linux-tools/kill-command-builder
- locate Command Builder: https://langstop.com/linux-tools/locate-command-builder
- ls Command Builder: https://langstop.com/linux-tools/ls-command-builder
- mkdir Command Builder: https://langstop.com/linux-tools/mkdir-command-builder
- mv Command Builder: https://langstop.com/linux-tools/mv-command-builder
- nmap Command Builder: https://langstop.com/linux-tools/nmap-command-builder
- ping Command Builder: https://langstop.com/linux-tools/ping-command-builder
- ps Command Builder: https://langstop.com/linux-tools/ps-command-builder
- rm Command Builder: https://langstop.com/linux-tools/rm-command-builder
- rmdir Command Builder: https://langstop.com/linux-tools/rmdir-command-builder
- sed Command Builder: https://langstop.com/linux-tools/sed-command-builder
- sort Command Builder: https://langstop.com/linux-tools/sort-command-builder
- ss Command Builder: https://langstop.com/linux-tools/ss-command-builder
- ssh Command Builder: https://langstop.com/linux-tools/ssh-command-builder
- stat Command Builder: https://langstop.com/linux-tools/stat-command-builder
- tar Command Builder: https://langstop.com/linux-tools/tar-command-builder
- touch Command Builder: https://langstop.com/linux-tools/touch-command-builder
- tree Command Builder: https://langstop.com/linux-tools/tree-command-builder
- wget Command Builder: https://langstop.com/linux-tools/wget-command-builder
- Cron Helper: https://langstop.com/cron-helper

## AI & LLM Tools

Craft and manage prompts for ChatGPT, Claude, Gemini, and other LLMs. Token counter included.

- AI Prompt Generator: https://langstop.com/ai-prompt-generator
- AI Prompt Editor: https://langstop.com/ai-prompt-generator/editor
- AI Prompt Workspaces: https://langstop.com/ai-prompt-generator/workspaces
- LLM Token Counter: https://langstop.com/text-utils/llm-token-counter

## Workflow & Pipeline Tools

Visual pipeline builder and JSON transform for chaining data operations.

- Pipeline Builder: https://langstop.com/pipeline-builder
- JSON Transform: https://langstop.com/json-transform

## Career & Resume Tools

Build and export developer resumes. Client-side only — no data uploads.

- Resume Builder: https://langstop.com/resume-builder

## Learning Resources

- What is JSON: https://langstop.com/what-is-json
- What is YAML: https://langstop.com/what-is-yaml
- What is XML: https://langstop.com/what-is-xml
- What is Base64: https://langstop.com/what-is-base64
- What is JWT: https://langstop.com/what-is-jwt
- JSON vs YAML: https://langstop.com/json-vs-yaml
- JSON vs XML: https://langstop.com/json-vs-xml
- YAML vs TOML: https://langstop.com/yaml-vs-toml

## All Tools

Browse all 180+ tools: https://langstop.com/tools

## Pricing

All tools are completely free. No pricing tiers. No signup required. No server uploads — everything runs in your browser.