Free online ASCII converter tool. Convert text to ASCII character codes (decimal, hex, binary, octal) and decode ASCII codes back to readable text instantly. Perfect for learning the ASCII table, debugging network protocols, and understanding character encoding fundamentals. 100% browser-based with zero uploads.
100% browser-based — your data never leaves your device
Convert text to ASCII codes and ASCII codes back to text instantly.
Type text to convert to ASCII codes, or paste comma/space-separated ASCII numbers to decode.
Toggle between text-to-ASCII and ASCII-to-text modes.
Click Copy to grab the converted output for use in your project.
Ctrl+Enter to convert
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This tool moves in both directions, text becomes a list of decimal ASCII codes and numeric codes become readable text, with bulk input handled in a single pass.
Decimal output is the default, and the whole conversion runs locally in your browser.
Low-level data work is where this tool earns its keep. Serial communication, embedded system logs, and protocol payloads frequently arrive as streams of numeric codes, and decoding them back into readable text turns cryptic output into something you can actually act on. The bulk conversion feature means you can paste a whole log block rather than decoding values one at a time.
On the teaching side, the tool makes character encoding tangible. Converting Hello into 72 101 108 108 111, then decoding it back, demonstrates exactly how computers represent letters as numbers. Because standard ASCII only defines codes 0 to 127, it is also a useful boundary-checking tool: characters outside that range immediately stand out as non-ASCII, which is itself useful information when debugging encoding mismatches.
The content you convert is often a protocol payload or embedded-system log that carries real operational data. Uploading it to a remote converter would expose details of your systems to a third party.
Local conversion keeps every code and every decoded character on your device. Debugging sessions and teaching materials never leave your browser.
Type text to convert to ASCII codes, or paste comma/space-separated ASCII numbers to decode.
Toggle between text-to-ASCII and ASCII-to-text modes.
Click Copy to grab the converted output for use in your project.
Practical examples to help you get the most out of ASCII Converter:
Input: 'Hello' Output: 72 101 108 108 111
Input: '83 117 99 99 101 115 115' Output: 'Success'
ASCII code input should use spaces between numbers. '72 101 108' is correct, '72,101,108' may not parse properly. The tool accepts both, but space-separated is the standard format.
'A' has ASCII code 65, not 1. ASCII codes for uppercase letters start at 65 (A-Z = 65-90). Lowercase letters start at 97 (a-z = 97-122).
ASCII (American Standard Code for Information Interchange) is a character encoding standard that assigns numeric values (0-127) to letters, digits, punctuation, and control characters.
By default, the tool outputs decimal ASCII codes. Each character's numeric value from 0-127 is shown.
Switch to the decode mode and enter ASCII code numbers separated by spaces or commas. The tool converts them back to readable text.
No. All conversion happens locally in your browser. Nothing is uploaded.
Convert any text string to decimal ASCII character codes instantly.
Decode ASCII code numbers back into their corresponding characters.
Process entire paragraphs or code blocks at once.
Copy the converted output directly to your clipboard.
ASCII Converter is useful in a variety of scenarios across different workflows:
Converting text to ASCII codes for low-level data processing
Decoding ASCII codes from serial communication and embedded systems
Learning and teaching ASCII character encoding fundamentals
Standard ASCII only defines codes 0-127. Characters beyond this range (like é, ñ, ü) are not part of ASCII and will show as 'unknown' or be handled by extended ASCII/Unicode.
Decimal ASCII codes (65 for 'A') are the most common and widely understood. Hex codes are useful for low-level programming and debugging.
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