ASCII Table

Complete ASCII code reference table with all 128 characters in decimal, hexadecimal, octal, and binary formats. Searchable and sortable for quick lookup.

ASCII character code {code} detail: symbol, decimal, hex, octal, binary. Part of the full ASCII code reference table.

ASCII Table - Character Code Chart Reference

ASCII Character {code} - Code Chart Detail

ASCII Table, American Standard Code for Information Interchange

Devtool.tech was built to give developers a single place for common tasks: encoding and decoding, format conversion, color utilities, and quick parsers. All tools run in your browser where possible, so your data stays on your device. We focus on speed and clarity: no sign-up, no paywall, and no clutter. Whether you need to decode a JWT, convert a color from hex to OKLCH, turn a CSV into Markdown, or check contrast ratios, you can do it here. The site is maintained with regular updates and new tools based on community feedback. We also care about accessibility and internationalization: the toolbox is available in English and Chinese, and we aim to keep interfaces keyboard-friendly and screen-reader friendly. If you have ideas for new tools or improvements, use the Contact page to send feedback. Thank you for using Developer's Arsenal.

About

Developer's Arsenal (devtool.tech) is a free online toolbox for programmers with 60+ professional tools for encoding, image processing, color conversion, and more.

About Us - Developer's Arsenal Overview

About Developer's Arsenal

ASCII Art Generator

Options

Convert images to ASCII character art online. Choose from multiple character sets, adjust output width. Free, runs entirely in the browser.

ASCII Art Generator - Image to Text Art

Base64 Encoding and Decoding

Free online encoder and decoder for text and binary data. Converts to and from the standard 64-character encoding with UTF-8 support. Essential developer tool.

Base64 Encoder & Decoder - Online Converter

Add webpage URLs to convert to Markdown, up to 10 URLs supported

Batch URL to Markdown Tool

Convert multiple webpage URLs to Markdown format simultaneously. Supports individual and batch ZIP download, processing up to 10 URLs per batch. Free tool.

Batch URL to Markdown - Multi-page Converter

Base Converter

Convert between binary, octal, decimal, and hexadecimal number systems instantly. Supports large number arithmetic. Free online tool for developers and students.

Base Converter - Binary, Octal, Hex, Decimal

CSS Color Names

Browse all 148 CSS named colors with RGB, HSL values, and live previews. Searchable reference table for front-end developers and web designers.

CSS Color Names - All 148 Named Colors Reference

Unicode Codepoint

Convert characters to Unicode code points online. View Unicode names, categories, and encoding details for any character. Free online encoding reference tool.

Unicode to Code Point - Character Encoder

Color Blindness Simulator

Simulate how colors appear to people with Protanopia, Deuteranopia, Tritanopia, and other color vision deficiencies. Optimize your designs for accessibility.

Color Blindness Simulator - Test Color Accessibility

Analyze contrast between original and grayscale colors with white background

Color Grayscale Calculator

Calculate grayscale values for any color online. Supports HEX, RGB, HSL, and more color formats. Ideal for designers and developers working with color accessibility.

Color Grayscale Calculator - Convert to Gray

Select preset colors to quickly view grayscale conversion effects

Color Harmony Generator

Generate harmonious color schemes based on color theory. Supports complementary, split-complementary, triadic, tetradic, analogous, and double complementary palettes.

Color Harmony Generator - Create Color Schemes

Color Luminance Online Calculator

Calculate relative luminance values for any color in real-time. Essential tool for designers and developers checking color contrast and readability standards.

Color Luminance Calculator - Measure Brightness

Color Mixer

Smoothly blend two colors with adjustable steps. Mix in RGB or HSL color spaces, generate CSS gradient code instantly. Free online color mixing tool for designers.

Color Mixer & Blender - Blend Two Colors

Color Convert

Convert colors between RGB, HSL, CMYK, and hexadecimal formats online. Pick any color and instantly get all format values. Essential tool for designers.

Color Converter - RGB, HSL, CMYK, HEX Tool

Color Palette Generator

Generate tint and shade color scales for design systems. Export palettes as CSS custom properties or Tailwind CSS config. Free online palette generator tool.

Color Palette Generator - Tint & Shade Scales

Preview Markdown

Click the examples below to quickly experience different types of string encoding

Quick String Examples

Clean template suitable for blog articles

Blog Post

Creative Design

Presentation

Perfect template for social media sharing

Social Media

Input History

Enter image title

Title cannot exceed 50 characters

Title is required

We welcome feedback from users and teams. Whether you found a bug, have an idea for a new tool, or want to discuss partnership and integration, getting in touch helps us prioritize and improve. Please use the feedback form below for feature requests, bug reports, or general questions; we read all submissions and use them to plan updates. For time-sensitive or security-related issues, we recommend including clear steps to reproduce and your environment (browser and OS) so we can respond quickly. We do not offer dedicated technical support for third-party integrations, but we are happy to consider documentation or tool improvements that would help. Thank you for helping make Developer's Arsenal better.

Contact

Contact the Developer's Arsenal team for product feedback, partnership inquiries, bug reports, and support questions. Reach us via form or email for a quick response.

Contact Us - Feedback & Partnership | Developer's Arsenal

Contact Us

Contrast Ratio, the difference in contrast between text color and background color, is extremely helpful for users with color vision deficiency.

Color Contrast Ratio Demo Page

Contrast Ratio Calculator

Check color contrast ratios for WCAG accessibility compliance. Input background and text colors for instant contrast calculation and AA/AAA level validation.

Contrast Ratio Calculator - WCAG Color Checker

The <wcag>Web Content Accessibility Guidelines (WCAG)</wcag> specify that for AA level, the contrast ratio should be greater than 4.5:1, and for large text, it should be greater than 3:1. For AAA level, the contrast ratio should be greater than 7:1, and for large text, it should be greater than 4.5:1.

Image DataURL Generator and Previewer

Free online tool to generate and preview image DataURLs. Convert images to base64 encoded DataURLs for web development use.

Image DataURL Generator and Previewer | Developer's Toolbox

Convert images to Base64 Data URI format online. Preview encoded results instantly, copy DataURL for inline embedding in HTML and CSS. Free developer tool.

Image DataURL Generator - Base64 Encoder

Apifox

Base64 encoding and decoding with internal principle demonstration

Base64 Encoding Explained

Convert multiple webpages to Markdown format in bulk, with options for individual or ZIP download

Batch URL To Markdown

Convert between binary, octal, and hexadecimal

Binary Converter

Simulate how colors appear to people with color vision deficiency

Generate harmonious color schemes based on color theory

Color Luminance Calculator

Blend two colors and generate smooth gradient transitions

Color Palette

Color Contrast Ratio Calculator

Online CSV table generator, create CSV tables by specifying rows and columns, with copy and download support

CSV Generator

Online CSV to HTML table converter, quickly convert CSV data to HTML table format, with copy and download support

CSV to HTML Table

Online CSV to JSON converter, quickly convert CSV data to JSON format, with copy and download support

CSV to JSON

Online CSV to LaTeX table converter, quickly convert CSV data to LaTeX table format, with copy and download support

CSV to LaTeX Table

Online CSV to Markdown table converter, quickly convert CSV data to Markdown table format, with copy and download support

CSV to Markdown Table

Online CSV to SQL INSERT converter, quickly convert CSV data to SQL INSERT statements, with copy and download support

CSV to SQL INSERT

Online CSV to YAML converter, quickly convert CSV data to YAML format, with copy and download support

CSV to YAML

Online Excel to CSV converter, quickly convert Excel spreadsheet data to CSV format, with copy and download support

Excel to CSV

Online Excel to HTML table converter, quickly convert Excel spreadsheet data to HTML table format, with copy and download support

Excel to HTML Table

Online Excel to JSON converter, quickly convert Excel spreadsheet data to JSON format, with copy and download support

Excel to JSON

Online Excel to Markdown table converter, quickly convert Excel spreadsheet data to Markdown table format, with copy and download support

Excel to Markdown Table

View and strip EXIF metadata from JPEG images

JPEG Metadata Viewer & Stripper

Generate all favicon sizes from a single image, with HTML code snippets

Favicon Generator

Front-end Tech Stack Icons

Detect file type based on binary magic numbers

File Type Detector

CSS Gradient Generator

Online generation of MD5, SHA1, SHA256, SHA512

Hash Generator

Free online HTML entity encoding and decoding service

HTML Entity Encoding

Online HTML table generator, create HTML tables by specifying rows and columns, with copy and download support

HTML Table Generator

Online HTML table to CSV converter, quickly convert HTML table data to CSV format, with copy and download support

HTML Table to CSV

Online HTML table to JSON converter, quickly convert HTML table data to JSON format, with copy and download support

HTML Table to JSON

Online HTML table to LaTeX converter, quickly convert HTML table data to LaTeX table format, with copy and download support

HTML Table to LaTeX

Real-time HTML to Markdown conversion, supporting complex syntax like tables and code blocks

HTML To Markdown

Online HTML table to SQL INSERT converter, quickly convert HTML table data to SQL INSERT statements, with copy and download support

HTML Table to SQL INSERT

Online HTML table to YAML converter, quickly convert HTML table data to YAML format, with copy and download support

HTML Table to YAML

Internal representation of IEEE 754 double-precision floating-point numbers

IEEE 754 Illustration

Extract dominant color palette from uploaded images

Image Color Extractor

Use Github repository as your personal image hosting

MicroGallery - Personal Image Hosting

Image Grayscale Generator

Image placeholder generator and API, customizable height, width, color, etc.

Image Placeholder API

Image Share Link Generator

Extract dominant colors from images and generate CSS gradients

Image to CSS Gradient

Add text watermarks to images with customizable position, opacity, and style

Image Watermark

IP Info

Online JSON table generator, create JSON data by specifying rows and columns, with copy and download support

JSON Generator

Online JSON to CSV converter, quickly convert JSON data to CSV format, with copy and download support

JSON to CSV

Online JSON to HTML table converter, quickly convert JSON data to HTML table format, with copy and download support

JSON to HTML Table

Online JSON to LaTeX table converter, quickly convert JSON data to LaTeX table format, with copy and download support

JSON to LaTeX Table

Online JSON to Markdown table converter, quickly convert JSON data to Markdown table format, with copy and download support

JSON to Markdown Table

Online JSON to SQL INSERT converter, quickly convert JSON data to SQL INSERT statements, with copy and download support

JSON to SQL INSERT

Online JSON to YAML converter, quickly convert JSON data to YAML format, with copy and download support

JSON to YAML

Decode and validate JSON Web Tokens with detailed information

JWT Decoder & Validator

Create and sign JSON Web Tokens with custom payloads and signing algorithms

JWT Encoder

Online LaTeX table generator, create LaTeX tables by specifying rows and columns, with copy and download support

LaTeX Table Generator

Markdown CV

Online Markdown editor with WeChat theme support

Markdown Code Editor

Convert between Markdown tables, CSV, and JSON formats

Markdown Table Generator

Online Markdown table generator, create Markdown tables by specifying rows and columns, with copy and download support

Markdown Table Generator Page

Online Markdown table to CSV converter, quickly convert Markdown table data to CSV format, with copy and download support

Markdown Table to CSV

Online Markdown table to HTML converter, quickly convert Markdown table data to HTML table format, with copy and download support

Markdown Table to HTML

Online Markdown table to JSON converter, quickly convert Markdown table data to JSON format, with copy and download support

Markdown Table to JSON

Online Markdown table to LaTeX converter, quickly convert Markdown table data to LaTeX table format, with copy and download support

Markdown Table to LaTeX

Online Markdown table to SQL INSERT converter, quickly convert Markdown table data to SQL INSERT statements, with copy and download support

Markdown Table to SQL INSERT

Online Markdown table to YAML converter, quickly convert Markdown table data to YAML format, with copy and download support

Markdown Table to YAML

Debug and test npm libraries online in the browser console

NPM Online Execution

Free online OCR tool supporting text recognition in multiple languages, based on Tesseract.js technology

Image Watermark

Watermark Options