ASCII Table Reference

Browse the complete ASCII character table (0–127) with decimal, hex, octal, binary, HTML entity, and control character names; filter by code or name

Key Facts

Category
Developer & Web
Input Types
checkbox, select
Output Type
html
Sample Coverage
3
API Ready
Yes

Overview

The ASCII Table Reference is an interactive lookup tool for the complete 7-bit ASCII character set (0–127). It provides instant access to decimal, hexadecimal, octal, binary, HTML entities, and control character representations, with built-in filtering and highlighting options to streamline development and debugging workflows.

When to Use

  • •When debugging low-level network protocols or serial communications where you need to map raw bytes to ASCII control characters.
  • •When writing HTML or web content and you need to find the correct HTML entity or decimal code for special symbols.
  • •When programming character validation logic and you need to verify the exact decimal or hex boundaries for uppercase, lowercase, or numeric ranges.

How It Works

  • •Toggle the visibility of control characters (0–31, 127) or printable characters (32–126) to narrow down the displayed set.
  • •Apply a letter case filter to isolate uppercase letters, lowercase letters, digits, or punctuation and symbols.
  • •Select a highlight range to visually emphasize specific character groups like letters, digits, or control codes in the table.
  • •Read the corresponding decimal, hexadecimal, octal, binary, and HTML entity values directly from the generated interactive table.

Use Cases

Finding the hexadecimal representation of control characters like Line Feed (LF) or Carriage Return (CR) for parser configuration.
Looking up HTML entity codes for symbols and punctuation to prevent rendering issues in web browsers.
Verifying binary and octal values of characters when writing low-level bitwise operations or embedded systems code.

Examples

1. Identifying Control Characters in Network Logs

Network Engineer
Background
A network engineer is analyzing raw packet payloads and encounters non-printable bytes like 0x0A and 0x0D.
Problem
They need to quickly identify which control characters these hex values represent.
How to Use
Enable 'Show Control Characters', set the highlight range to 'Control', and locate the hex values 0A and 0D in the table.
Example Config
Show Control Characters: enabled, Highlight Range: control
Outcome
The engineer identifies 0x0A as Line Feed (LF) and 0x0D as Carriage Return (CR), confirming the payload uses standard Windows-style line endings.

2. Validating Input Ranges for Form Fields

Frontend Developer
Background
A developer is writing a JavaScript keypress handler to restrict input to lowercase letters only.
Problem
They need to know the exact decimal range for lowercase letters (a-z) to set up boundary conditions.
How to Use
Select 'Lowercase Letters' from the Letter Case Filter and check the decimal column for the start and end values.
Example Config
Letter Case Filter: Lowercase Letters
Outcome
The table filters to show codes 97 (a) through 122 (z), providing the exact decimal boundaries needed for the validation script.

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FAQ

What is the range of characters covered by this ASCII table?

The table covers the standard 7-bit ASCII range from 0 to 127, including both control and printable characters.

Can I filter the table to show only numbers or letters?

Yes, you can use the Letter Case Filter to display only digits, uppercase letters, lowercase letters, or punctuation.

Does this tool support extended ASCII characters above 127?

No, this reference tool is strictly for the standard 7-bit ASCII character set (codes 0–127).

How do I find the HTML entity for a specific character?

Locate the character in the table to view its corresponding HTML entity representation in the dedicated column.

Can I hide control characters like NUL, LF, or CR?

Yes, uncheck the 'Show Control Characters' option to hide codes 0–31 and 127 from the table view.

API Documentation

Request Endpoint

POST /en/api/tools/ascii-table

Request Parameters

Parameter Name Type Required Description
showControl checkbox No -
showPrintable checkbox No -
caseFilter select No -
highlightRange select No -

Response Format

{
  "result": "
Processed HTML content
",
  "error": "Error message (optional)",
  "message": "Notification message (optional)",
  "metadata": {
    "key": "value"
  }
}
HTML: HTML

AI MCP Documentation

Add this tool to your MCP server configuration: 

{
  "mcpServers": {
    "elysiatools-ascii-table": {
      "name": "ascii-table",
      "description": "Browse the complete ASCII character table (0–127) with decimal, hex, octal, binary, HTML entity, and control character names; filter by code or name",
      "baseUrl": "https://elysiatools.com/mcp/sse?toolId=ascii-table",
      "command": "",
      "args": [],
      "env": {},
      "isActive": true,
      "type": "sse"
    }
  }
}

You can chain multiple tools, e.g.: `https://elysiatools.com/mcp/sse?toolId=png-to-webp,jpg-to-webp,gif-to-webp`, max 20 tools.

If you encounter any issues, please contact us at [email protected]