What counts as valid ASCII here?

Strict 7-bit ASCII: character codes 0 through 127 only, covering standard English letters, digits, punctuation, and control characters. Extended (8-bit) or Unicode characters above 127 are rejected rather than silently mis-encoded.

Why is the notation "U+00XX" and not just "U+X"?

"U+" followed by at least 4 hex digits is the standard way the Unicode Consortium and most software display code points, so a 2-digit ASCII code like 65 (0x41) is padded to "U+0041" for consistency with how any Unicode code point is normally written.

What happens if my text has a non-ASCII character?

Conversion stops at that character and the error names exactly which character it was, its position in the text, and its code point.

How is this different from the String to Hex Converter?

String to Hex Converter accepts the full Unicode range and outputs bare 2-digit hex pairs with no "U+" prefix and no strict range check. This tool specifically enforces strict 7-bit ASCII (0-127), rejects anything outside that range, and formats output in the "U+00XX" notation that's the standard way to write Unicode code points, rather than raw hex bytes.

ASCII to Unicode Code Point Converter

Overview

Introduction

"U+" notation is the standard way to write a Unicode code point, U+0041 for the letter 'A', for example, and it's a useful bridge between plain ASCII text and the wider Unicode character set it's a subset of.

This tool converts plain text to its code points in that notation, one per character, while strictly enforcing that every character actually fits in the 7-bit ASCII space.

What Is ASCII to Unicode Code Point Converter?

A text-to-code-point encoder that walks each character of the input, looks up its ASCII code, and formats that code as "U+" followed by at least 4 uppercase hex digits.

Unlike a general Unicode-aware converter, it treats any character above code 127 as an error condition rather than something to encode, since the point of this tool is verifying and displaying strict ASCII in Unicode notation.

How ASCII to Unicode Code Point Converter Works

The input is split into individual characters by Unicode code point (so multi-unit characters like emoji are handled as a single unit), and each character's code point is checked against the 0-127 range.

If every character passes, each one is converted to hexadecimal, uppercased, left-padded to at least 4 digits, prefixed with "U+", and joined with single spaces in original order. If any character fails the check, conversion stops immediately and reports that character.

When To Use ASCII to Unicode Code Point Converter

Use it when you need to see or document ASCII text's code points in standard Unicode notation, for example writing technical documentation, regex character class references, or Unicode-aware test fixtures.

If your text might contain accented letters, emoji, or any non-English script, use String to Hex Converter or a general Unicode code point tool instead, since this one will reject anything above 127.

Often used alongside Unicode to ASCII Converter, String to Hex Converter and ASCII to Hex Converter.

Features

Advantages

Catches non-ASCII characters immediately with a precise error instead of silently producing an incorrect code point.
Uses the exact "U+XXXX" notation standard technical documentation and the Unicode Consortium itself use.
Reports the exact character and position of any validation failure, making it fast to locate and fix problem input.

Limitations

Cannot encode any text containing accented letters, non-Latin scripts, emoji, or other characters above code point 127; it errors out instead.
Treats control characters (like newline or tab) as valid ASCII and encodes them, which is correct but can be surprising if you expect only printable output.

Examples

Encoding a simple word

Input

Hi

Output

U+0048 U+0069

'H' (72 decimal, 0x48) and 'i' (105 decimal, 0x69) are each formatted as U+ notation with at least 4 hex digits.

Encoding a control character

Input

Output

U+0041 U+000A

The newline character (code 10, 0x0A) encodes the same as any other ASCII code point, just often invisible when rendered.

Rejecting a non-ASCII character

Input

Héllo

Output

Character "é" at position 2 has code point 233 (0xE9), which is outside the 7-bit ASCII range (0-127).

'é' is code point 233, above the 127 limit, so conversion is rejected rather than encoding it incorrectly.

Best Practices & Notes

Best Practices

If you're not sure your text is pure ASCII, run it through this tool first; a rejection is a fast, precise way to confirm the presence and location of any non-ASCII character.
For text you know or expect to include international characters, reach for a general Unicode code point or String to Hex Converter tool instead of fighting this tool's validation.

Developer Notes

Implemented by splitting the input with `Array.from(input)` (iterating by Unicode code point rather than UTF-16 code unit) via the shared `validateStrictAscii` helper, then formatting each code point with `` `U+${codePoint.toString(16).toUpperCase().padStart(4, "0")}` ``.