How to Look Up ASCII Codes in Dec, Hex and Binary

To look up an ASCII code, open the interactive table, type the character, number or name into the search box, and read its decimal, hexadecimal, octal and binary values from the row — all four bases lined up side by side. The ByteTools ASCII Table covers codes 0 to 127, with an optional extended range of 128 to 255, and filters instantly as you type. Here is how to use it and how to read what it shows.

What the ASCII table shows

ASCII maps the numbers 0 to 127 onto letters, digits, punctuation and control codes. For each code, the table displays five things at once: the decimal value, the hexadecimal value, the octal value, the binary value, the printable glyph (or a name for invisible codes) and a short description. Seeing every base together means you never have to convert by hand — the letter A is 65, 0x41, 0o101 and 01000001 in one glance.

Step-by-step: finding any code

1. Browse or search. The table lists codes 0 to 127 by default. Scroll to explore, or jump straight to what you need with the search box.
2. Type your query. Enter a character (like @), a number (like 64), a hex value, or a name (like TAB). The table filters to matching rows as you type.
3. Read across the row. Each column gives a different base — decimal, hex, octal, binary — plus the character and description.
4. Enable the extended range if needed. Tick "Include extended (128–255)" to reveal the Latin-1 range with accented letters and extra symbols.

Reading control characters

Codes 0 to 31, plus 127, are control characters — they trigger actions rather than printing a symbol. The table names and describes each one so they are not a mystery:

These are the codes you meet constantly when debugging text, and having their meanings named saves a trip to a reference manual.

Why in-browser and private matters

The entire table is generated and filtered in your browser — there is nothing to upload and nothing to load from a server after the page opens. That means it works offline, responds instantly with no network round-trip, and never sees the characters you search for. For developers working on encoding, protocols or low-level debugging, it is a fast reference that stays out of your way and keeps your data local.

Try the ASCII Table — free and 100% in your browser.

FAQ

How do I find the ASCII code for a specific letter?

Type the letter into the search box. The table filters to its row and shows the decimal, hex, octal and binary codes. You can search the other direction too — enter a number to see which character it maps to.

How do I convert an ASCII code to hex or binary?

You do not have to convert anything — the table already lists every code in all four bases side by side. Find the row and read the hex or binary column directly.

What is the extended ASCII range and when do I need it?

Extended ASCII covers codes 128 to 255, used by encodings like Latin-1 for accented letters and extra symbols. Tick the extended option when you are working with characters beyond the standard 0–127 set.

Does the table work without internet?

Yes. Once the page has loaded, everything runs in your browser, so it keeps working offline and never sends your searches anywhere.

Related free tools

• Binary Calculator — do arithmetic and conversions in binary.
• Base64 Encoder — encode text and data to Base64.
• MIME Type Lookup — find the MIME type for any file extension.
• HTTP Status Code Lookup — decode any HTTP response code.

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