Are all tools completely free?

Yes. Every tool in DevTools Suite is free to use with no limits, no rate limits, and no premium tier. We sustain the platform through minimal, non-intrusive advertising.

Is my data uploaded to your servers?

No. All processing happens locally in your browser. We have no backend, no database, and no server that receives your content. Your JSON, tokens, regex patterns, and checklist items never leave your device.

Do the tools work offline?

Yes. After the initial page load, all tools function without an internet connection. The only features that require connectivity are AdSense ads and Google Analytics — both of which are non-essential.

Is login or an account required?

No. There are no accounts, no sign-up forms, and no email required. Open any tool and start using it immediately.

Do the tools work on mobile?

Yes. All tools are responsive and tested at 375px viewport width. Toolbars adapt to mobile layouts, and touch interactions are supported throughout.

How is my checklist saved between sessions?

The Smart Checklist saves your work to your browser's localStorage automatically. No account needed — your list is there when you come back, as long as you use the same browser.

Developer Tools, instantly in your browser

Privacy-first tools that run 100% locally. No login, no uploads, no tracking. Just open and use.

Open Smart Checklist Browse Tools

Runs locally

No signup

Privacy-first

Free forever

release-checklist

2/5 complete40%

Deploy database migrations
Run smoke tests
Update release notes
Notify stakeholders
Archive old builds

cron-generator

Minute

Hour

Day

Month

Weekday

1-5

Expression

0 9 * * 1-5

Meaning

At 9:00 AM, Monday through Friday

regex-tester

Pattern

/\d+/g

Test string

Deploy v2.14 on port 8080

2 matches

All Tools

Click any tool to open it instantly. No loading screens.

Smart Checklist

Featured

Organize tasks, workflows, and nested checklists with a fast, privacy-first checklist system.

Simple & Advanced modes — flat list or 3-level nested hierarchy
Shareable URLs — recipients get a named copy instantly
Export to PDF, Markdown, JSON, CSV, or plain text

nested tasksprogress trackingshareable60+ templatesauto-saved

Paste any list or start blank — simple or nested

New Workspace

Paste any list or start blank — simple or nested

60+ ready-made checklists across 16 categories

Templates

60+ ready-made checklists across 16 categories

Your saved checklists — pin, rename, duplicate

My Checklists

Your saved checklists — pin, rename, duplicate

JSON Formatter

Prettify, minify, validate and explore JSON with syntax highlighting.

json beautifierjson validator

Cron Generator

Build cron expressions visually. Supports Unix, AWS EventBridge and Spring.

cron buildercron parser

Diff Checker

Compare text side-by-side with line, character and JSON-aware diffing.

compare textjson diff

JWT Decoder

Decode JWT tokens and inspect claims without sending tokens anywhere.

decode jwtjwt inspector

Regex Tester

Test regular expressions live with match highlighting and replace preview.

regex checkerregex validator

Base64 Encoder / Decoder

Encode text to Base64 or decode Base64 strings back to plain text instantly.

base64 encoderbase64 decoder

UUID Generator

Generate cryptographically random UUID v4 values. Copy one or all at once.

uuid v4guid generator

URL Encoder / Decoder

Percent-encode URLs or decode encoded URL strings — real-time conversion.

url encoderpercent encoding

Markdown Previewer

Write Markdown with a live GitHub-style preview. Sanitized and real-time.

markdown editorlive preview

SQL Formatter

Beautify or minify SQL queries with dialect-aware formatting. Supports MySQL, PostgreSQL, and more.

sql beautifierformat sql

Color Converter

Convert colors between HEX, RGB, and HSL with a live color swatch and picker.

hex to rgbcolor picker

Hash Generator

Generate MD5, SHA-1, SHA-256, and SHA-512 hashes using browser-native Web Crypto.

sha256md5 hash

YAML ↔ JSON Converter

Convert between YAML and JSON with validation and pretty-printing. Supports full YAML 1.2.

yaml to jsonjson to yaml

JSON → TypeScript

Generate typed TypeScript interfaces from JSON. Handles nested objects and arrays automatically.

json to typescriptts interfaces

CSV ↔ JSON Converter

Convert CSV to JSON or JSON arrays to CSV. Upload files or paste directly.

csv to jsonjson to csv

Timestamp Converter

Convert Unix timestamps to human-readable dates and vice versa. Supports seconds and milliseconds.

unix timestampepoch converter

Case Converter

Convert text between camelCase, snake_case, PascalCase, kebab-case, and more in real-time.

camelcasesnake_case

Password Generator

Generate cryptographically secure passwords with configurable length and character sets.

secure passwordrandom password

JWT Generator

Generate and sign JWT tokens locally with HS256. Edit header, payload, and secret live.

jwt signhs256 jwt

XML Formatter

Pretty-print or minify XML with validation. Reports errors with line numbers.

xml beautifierformat xml

QR Code Generator

Generate QR codes from any text or URL. Download as PNG. Adjustable size and colors.

qr codeqr generator

JSON → Zod Schema

Generate typed Zod schemas from JSON. Supports nested objects, arrays, and strict mode.

zod schematypescript zod

Flexbox Playground

Experiment with CSS Flexbox properties interactively. Live preview with generated CSS output.

css flexboxlayout tool

API Request Builder

Build and send HTTP requests from your browser. Inspect responses and copy cURL commands.

http clientrest tester

JSON Schema Generator

Generate JSON Schema (draft 2020-12) from any JSON object with nested object support.

json schemajson validation

Bcrypt Generator

Generate and verify bcrypt hashes locally. Adjustable salt rounds. No data transmitted.

bcrypt hashpassword hash

OpenAPI Viewer

Browse OpenAPI 3.x and Swagger specs locally. Search endpoints, view parameters and responses.

openapiswagger viewer

Tailwind Playground

Experiment with Tailwind CSS classes live. Desktop/mobile preview toggle and preset snippets.

tailwind csscss playground

JSON → Dart Models

Generate Dart model classes from JSON. Supports null safety and fromJson/toJson for Flutter.

dart modelflutter json

JSON → C# Classes

Generate C# model classes from JSON with PascalCase, System.Text.Json attributes, and namespaces.

c# modelcsharp json

Docker Compose Formatter

Beautify and validate docker-compose YAML files with minify support. Browser-only, no uploads.

docker composeyaml formatter

Why DevTools Suite?

Built for developers who value speed, privacy, and focus over feature bloat.

Your data never leaves your device

Every tool runs entirely in your browser using JavaScript. No file uploads, no API calls, no server processing. JWT tokens, JSON payloads, and diff content stay on your machine.

Faster than AI chat workflows

Open a tool, paste your content, get your result — in under a second. No prompting, no waiting for a model response, no copy-paste round trips.

Works offline after first load

Once the page loads, the tools work without an internet connection. Ideal for working in restricted environments, on flights, or with a spotty connection.

Built for keyboard-first developers

Every tool supports keyboard shortcuts, tab navigation, and accessible interactions. Designed for developers who prefer the keyboard over the mouse.

Frequently Asked Questions

Are all tools completely free?: Yes. Every tool in DevTools Suite is free to use with no limits, no rate limits, and no premium tier. We sustain the platform through minimal, non-intrusive advertising.
Is my data uploaded to your servers?: No. All processing happens locally in your browser. We have no backend, no database, and no server that receives your content. Your JSON, tokens, regex patterns, and checklist items never leave your device.
Do the tools work offline?: Yes. After the initial page load, all tools function without an internet connection. The only features that require connectivity are AdSense ads and Google Analytics — both of which are non-essential.
Is login or an account required?: No. There are no accounts, no sign-up forms, and no email required. Open any tool and start using it immediately.
Do the tools work on mobile?: Yes. All tools are responsive and tested at 375px viewport width. Toolbars adapt to mobile layouts, and touch interactions are supported throughout.
How is my checklist saved between sessions?: The Smart Checklist saves your work to your browser's localStorage automatically. No account needed — your list is there when you come back, as long as you use the same browser.