Developer Tools & Utilities

Professional collection of online developer tools including text processors, encoders/decoders, image converters, screen testing utilities, and calculation tools. All tools work offline and prioritize your privacy.

JSON Formatter

Beautify and validate JSON data format

Base64 Encoder/Decoder

Quick Base64 encoding and decoding

URL Encoder/Decoder

URL encoding and decoding tool

Keyword Density Analyzer

Analyze keyword frequency and density in text, support Chinese and English tokenization

TikTok Downloader

Download TikTok videos without watermark

MP4 Test Video Generator

Generate custom MP4 test videos with text/images and voice synthesis

Video to GIF

Convert videos to GIF animations online with custom settings

GIF to Video

Convert GIF animations to MP4, WebM, or MOV video formats

Extract Audio from Video

Extract audio from video files and save as MP3, WAV, or AAC

Video Format Converter

Convert videos between different formats with quality control

Video Resizer

Resize videos and change resolution to 4K, HD, or custom sizes

WebGPU Performance Test

Professional WebGPU vs Canvas2D performance comparison tool

Hash Generator

Generate MD5, SHA256 and other hash values

File Hash Calculator

Calculate file checksums with MD5, SHA-256, SHA-384, SHA-512, CRC32, xxHash, BLAKE3 using Rust+WASM

JWT Decoder

Parse and view JSON Web Token content

UUID Generator

Generate various versions of UUID

Sprite Animator

Convert sprite sheets to animations with frame selection and GIF export

Keyboard Tester

Visually test if keyboard keys are working properly

Timestamp Converter

Convert between timestamp and datetime

Date Calculator

Calculate date differences and date arithmetic

Password Generator

Generate secure random passwords (no data saved)

Color Code Converter

Convert between Hex, RGB, HSL and other color formats

Favicon Generator

Generate favicons in multiple sizes with customizable borders and backgrounds

Image Resizer

Resize images to any dimension with multiple output formats

Image to Base64 Converter

Convert images to Base64 encoding and vice versa with real-time preview

Image Format Converter

Convert images between PNG, JPG, and WebP formats with quality control

Image Puzzle Maker

Create image collages with drag-and-drop, snap-to-edges, and collision detection

Image Denoiser

Remove noise from images using advanced algorithms like Gaussian, Median, Bilateral and NLM filtering

Image Metadata Viewer

View and analyze EXIF metadata from images including camera settings, location data, and timestamps

Image Metadata Remover

Remove EXIF metadata from images to protect privacy and reduce file size

Image Watermark Tool

Add text or image watermarks to photos with customizable position, size, opacity and more

Color Picker from Image

Extract and analyze colors from any image with click-to-pick functionality

Image Rotate Tool

Rotate images to any angle or flip horizontally/vertically with real-time preview

Image to ASCII Art

Convert images to ASCII character art with color inversion and adjustable density

Long Image Generator

Combine multiple images and text blocks into long vertical images for social media and tutorials

Color Gamut Detector

Detect display color space support

Brightness Test

Test display brightness uniformity and backlight issues

Dead Pixel Test

Detect dead, stuck, or hot pixels on your display

Color Vision Test

Check color differentiation with common color blindness test patterns

Contrast Test

Test display contrast, sharpness, and edge clarity

Gradient Test

Detect color transition and banding issues

Reaction Speed Test

Click to start testing your reaction speed

FPS Aim Trainer

Professional FPS shooting training with aim, tracking, and flick shot modes

Refresh Rate Test

Detect display refresh rate (60Hz/120Hz/144Hz etc.)

Screen Resolution Test

Detect screen resolution, DPI, pixel ratio and scaling

Webcam Test

Test webcam quality, resolution and frame rate

Speaker Test

Test left/right channels, surround sound and audio frequencies

Touch Screen Test

Test multi-touch functionality and touch sensitivity

Case Converter

Convert text to various case formats, supports camelCase, snake_case, kebab-case and more

Find & Replace

Powerful text find and replace tool with regex support, case-sensitive and whole word matching options

Lorem Ipsum Generator

Generate Lorem Ipsum placeholder text by paragraphs, sentences, or words

Markdown Preview

Real-time Markdown preview with support for common Markdown syntax

Remove Duplicate Lines

Quickly remove duplicate lines from text with case-sensitive and order-preserving options

Text Diff Compare

Compare two texts and highlight added, removed, and modified content

Word & Character Counter

Count characters, words, lines, paragraphs and sentences in your text

Math Function Visualizer

Visualize common mathematical functions used in graphics programming with adjustable parameters

AABB Visualizer

Interactive 3D AABB construction and collision detection tool

Memory Layout Visualizer

Interactive 3D visualization comparing RGBA and NV12 pixel memory layouts

NV12 YUV Visualizer

Interactive 3D visualization of YUV color space, NV12 4:2:0 chroma subsampling, and memory layout

DNS Lookup

Query domain name DNS records and IP addresses in real-time

Cron Generator

Create and test cron expressions with presets, custom expressions and next run prediction

HTML Minifier

Minify HTML code, remove comments and whitespace

JS Minifier

Minify JavaScript code (Terser), reduce file size

CSS Minifier

Minify CSS code (clean-css), optimize loading

Favicon Fetcher

Fetch website favicons in multiple sizes using Google's API

Regex Tester

Test and validate regular expressions with real-time matching and highlighting

Roco Kingdom Toolbox

Browse dexes, track sessions, check matchups, and plan coverage in one place

Roco Kingdom Spirit Dex

Browse spirit attributes, base stats, abilities, and linked skills

Roco Kingdom Egg Dex

Browse egg art, spirit numbers, and element entry points

Roco Kingdom Skill Dex

Explore skill element, category, energy, power, and linked spirits

Roco Kingdom Egg Query

Look up likely hatch results by egg length and weight

Type Chart

View the full matchup matrix across 18 elements

Chroma Particle Dex

Compare Roco chroma color pairs and particle previews

PVP Coverage Calculator

Build 6v6 teams with 4-skill sets to analyze coverage, threats, and gaps

Changelog

Review Roco toolbox changlog, changelog, and maintenance notes

Why Use This Tools Hub

Browse every major tool category from one page

Jump straight into the right workflow without hunting through menus

Many tools run directly in the browser for faster iteration

Useful for developers, creators, testers, and power users alike

Frequently Asked Questions

What kinds of tools can I find here?

This page groups together developer tools, text processors, image utilities, video helpers, graphics demos, detection tools, and the Roco toolbox so you can browse by category.

Are these tools free to use?

Yes. The tools in this hub are designed for quick online use without registration, so you can open a page and start working right away.

Do all tools process data locally?

Many tools run directly in the browser, while a few network-oriented tools may call external services when the feature itself depends on remote data. Each tool page explains its own privacy behavior.