All-in-One Toolbox
A collection of fast, free, and privacy-focused online tools, including text processing, image editing, file conversion, and programming development and more. No download required, use instantly to boost productivity.
Why Choose DevToolBox?
Built with modern web technologies for the best user experience
Privacy First
Your data never leaves your device. All processing happens locally in your browser using client-side JavaScript. No servers, no tracking, no data collection - ever.
Lightning Fast
Get instant results with zero server delays. No waiting, no loading spinners. Works perfectly offline once loaded, so you can use tools anywhere, anytime.
100% Free Forever
All tools are completely free with no hidden costs, premium tiers, or paywalls. No ads cluttering your workspace. No credit card required. Just pure functionality.
Easy to Use
Clean, intuitive interface designed for everyone. No manuals needed. Responsive design works flawlessly on desktop, tablet, and mobile devices.
All-in-One Toolbox
Everything you need in one place. From data encoding to color picking, hash generation to JSON formatting - access dozens of tools without switching between websites or apps.
Always Available
No server downtime or maintenance windows. Since everything runs in your browser, tools are available 24/7/365. Bookmark and use anytime you need.
Popular Tools
Powerful tools that run entirely in your browser. No servers, no tracking, just pure functionality.
Random Password Generator
Generate strong, secure random passwords with customizable length and character types. Support bulk generation and password strength analysis.
Free Online CSV Viewer - View & Analyze CSV Files Instantly
Free online CSV viewer to open, view and analyze CSV files in browser. No installation needed. Support large files, search, filter, sort and export. Paste CSV data or upload files. 100% secure and private.
Daily Water Intake Calculator
Free water intake calculator to determine your personalized daily hydration needs based on weight, activity level, climate, and health conditions. Get accurate water consumption recommendations in liters, glasses, and bottles to stay properly hydrated.
Compound Interest Calculator
Calculate compound interest growth for investments and savings. See how your money grows over time with regular contributions and compound returns.
URL Link Batch Generator
Generate multiple URLs with sequential numbering and customizable patterns instantly. Perfect for creating test URLs, generating link lists, batch URL creation, SEO testing, and web scraping preparation.
Text Duplicate Detector
Find and remove duplicate lines in text instantly. Detect repeated content, clean data lists, identify unique entries with detailed statistics. Perfect for data cleaning, email lists, and content deduplication.
Keyboard KeyCode Viewer - JavaScript Key Event Inspector
Interactive JavaScript keyboard event inspector. Press any key to instantly view keyCode, key, code, which, charCode, and modifier states. Essential debugging tool for web developers building keyboard shortcuts and event handlers.
Screen Color Picker
Pick colors from anywhere on your screen with eyedropper tool. Get HEX, RGB, HSL color codes instantly for design and development.
Image Format Converter
Convert images between formats online - JPG, PNG, WebP, GIF, BMP. Fast, free image conversion with quality control and batch processing.
Video Player - Play MP4, WebM, AVI & More Video Formats Online
Free online video player supporting MP4, WebM, AVI, MOV and more formats. Play videos with full controls, speed adjustment, and quality settings. No installation required.
TI-84 Calculator Online
Free online TI-84 Plus CE graphing calculator simulator with zoom and fullscreen support. Perform advanced math calculations, plot graphs, solve equations, and use statistical functions just like the real TI-84 Plus calculator.
Phone to VCF Converter - Batch Import Contacts to Address Book
Convert phone numbers to VCF (vCard) format for batch importing contacts. Support name assignment, carrier detection, and multiple export options. Perfect for CRM, marketing campaigns, and contact management.
What Users Say
Trusted by users worldwide
Sarah Chen
Full Stack Developer
DevToolBox has become an essential part of my daily workflow. The JSON formatter alone saves me hours every week. Love that everything runs locally!
Michael Rodriguez
Backend Engineer
Finally, a tool collection that respects privacy! No more uploading sensitive data to random websites. The Base64 encoder is incredibly fast and reliable.
Emily Watson
Frontend Developer
Clean UI, lightning-fast performance, and works offline. The color picker is my go-to tool for design work. Highly recommended!
David Kim
DevOps Engineer
The hash generator and UUID tools are perfect for my automation scripts. Being able to use them offline during deployments is a game-changer.
Sarah Chen
Full Stack Developer
DevToolBox has become an essential part of my daily workflow. The JSON formatter alone saves me hours every week. Love that everything runs locally!
Michael Rodriguez
Backend Engineer
Finally, a tool collection that respects privacy! No more uploading sensitive data to random websites. The Base64 encoder is incredibly fast and reliable.
Emily Watson
Frontend Developer
Clean UI, lightning-fast performance, and works offline. The color picker is my go-to tool for design work. Highly recommended!
David Kim
DevOps Engineer
The hash generator and UUID tools are perfect for my automation scripts. Being able to use them offline during deployments is a game-changer.
Lisa Anderson
Software Architect
I've tried many online tool collections, but DevToolBox stands out with its privacy-first approach and modern interface. The tools just work!
James Thompson
Mobile Developer
Great collection of tools that I use daily. The URL encoder and JSON formatter are particularly useful. No ads, no tracking - just pure functionality.
Alex Martinez
Security Engineer
As a security engineer, I appreciate tools that don't send data to external servers. The hash generator is perfect for quick verification tasks during code reviews.
Rachel Green
UI/UX Designer
The color picker tool is incredibly useful for my design work. Being able to convert between HEX, RGB, and HSL instantly saves so much time. The interface is intuitive too!
Lisa Anderson
Software Architect
I've tried many online tool collections, but DevToolBox stands out with its privacy-first approach and modern interface. The tools just work!
James Thompson
Mobile Developer
Great collection of tools that I use daily. The URL encoder and JSON formatter are particularly useful. No ads, no tracking - just pure functionality.
Alex Martinez
Security Engineer
As a security engineer, I appreciate tools that don't send data to external servers. The hash generator is perfect for quick verification tasks during code reviews.
Rachel Green
UI/UX Designer
The color picker tool is incredibly useful for my design work. Being able to convert between HEX, RGB, and HSL instantly saves so much time. The interface is intuitive too!
Tom Wilson
Data Engineer
I work with a lot of encoded data and APIs. The Base64 and URL encoder tools are lifesavers. Fast, accurate, and no need to worry about data privacy issues.
Nina Patel
QA Engineer
Testing APIs requires a lot of data manipulation. DevToolBox has all the tools I need in one place. The JSON formatter with validation is particularly helpful for debugging.
Chris Johnson
Tech Lead
I've recommended DevToolBox to my entire team. It's become our go-to resource for quick data transformations. The fact that it works offline is a huge plus during travel.
Sophie Laurent
API Developer
Working with webhooks and API integrations means dealing with lots of encoded data. These tools are exactly what I need - simple, fast, and trustworthy. No bloat, just functionality.
Tom Wilson
Data Engineer
I work with a lot of encoded data and APIs. The Base64 and URL encoder tools are lifesavers. Fast, accurate, and no need to worry about data privacy issues.
Nina Patel
QA Engineer
Testing APIs requires a lot of data manipulation. DevToolBox has all the tools I need in one place. The JSON formatter with validation is particularly helpful for debugging.
Chris Johnson
Tech Lead
I've recommended DevToolBox to my entire team. It's become our go-to resource for quick data transformations. The fact that it works offline is a huge plus during travel.
Sophie Laurent
API Developer
Working with webhooks and API integrations means dealing with lots of encoded data. These tools are exactly what I need - simple, fast, and trustworthy. No bloat, just functionality.
Frequently Asked Questions
Everything you need to know about DevToolBox