What Characters Can You Use in a WiFi Password?

Published September 3, 2026

Short answer: WPA2 and WPA3 accept 8 to 63 printable ASCII characters — every letter, digit and punctuation mark on a standard keyboard. But what the specification allows and what your router, printer and smart TV actually handle are two different things. In practice, stick to this set:

Quotes, backslashes, backticks, semicolons, commas and spaces are legal in the spec, yet they are the exact characters that cause a WiFi password to be accepted by the router and then mysteriously rejected by a device. Below is why, and what to do instead.

What the WPA2/WPA3 specification actually allows

A WiFi password is technically called a PSK passphrase. The standard defines it as 8 to 63 characters of printable ASCII — that is character codes 32 through 126, which covers a–z, A–Z, 0–9, the space, and all common punctuation.

Two consequences people trip over:

• 8 characters is a hard floor. Routers will refuse to save anything shorter — it is not your router being awkward, it is the standard.
• 63 is a hard ceiling. Some admin panels silently truncate rather than warn you, which is one reason a password can stop matching after you save it.

Anything outside printable ASCII — accented letters, curly quotes, emoji, non-Latin scripts — is outside the specification. Devices then guess at the encoding, and two devices guessing differently means the same password works on one and fails on the other, with no useful error message.

The characters that cause real problems

These are all technically valid. They still break things:

Look-alike characters: legal, and still a mistake

A WiFi password is unusual in that it gets read aloud, copied off a sticker, or dictated over the phone. That makes visually ambiguous characters a practical problem even though no device objects to them:

• 0 versus O — zero and capital letter O
• l versus 1 versus I — lowercase L, one, capital i
• 5 versus S, 8 versus B, 2 versus Z

In many router-label fonts these are nearly identical. Our WiFi password generator has an Easy to type option that removes this whole class of character for you, so a guest reading the password off a card gets it right the first time.

The WiFi QR code trap

Sharing your network by QR code is convenient, and it has a sharp edge nobody mentions. The format encoded in the QR is a single text string:

Because ; and : are the field separators, the characters semicolon, colon, comma, backslash and double quote must be backslash-escaped inside the password. Plenty of QR generators simply do not do this — the code they produce looks perfectly normal and silently fails to connect, or connects with a mangled password.

Keeping those characters out of the password in the first place sidesteps the entire problem. It is one more reason the safe set above is worth sticking to. If you want a code that handles the escaping properly either way, our WiFi QR code generator escapes those five characters and tells you when it did.

Device-by-device: where passwords get entered

Before choosing a password, think about everything that will have to join the network:

• Smart TVs and streaming sticks. Entry is via a directional remote on an on-screen keyboard. Every symbol means switching keyboard layers — a 20-character password of letters and digits is genuinely faster to enter than a 12-character one full of punctuation.
• Games consoles. Same problem, with a controller instead of a remote.
• Printers. Often the worst case: a tiny keypad, limited character support, and setup wizards that reject symbols they cannot display.
• Smart plugs, cameras, IoT gadgets. Configured through a phone app, but the firmware behind it sometimes has a shorter internal buffer and truncates without saying so.
• Guests. They will read it off whatever you wrote it on. This is where look-alike characters and capitalisation cost you.

My WiFi password looks right but will not connect

When a password you are certain about keeps getting rejected, check these in order:

1. Capitalisation. WiFi passwords are case-sensitive. Phone keyboards auto-capitalise the first letter — a very common cause.
2. Look-alike characters. Re-read for 0/O and l/1/I. Try the alternative reading.
3. Trailing space. Copying from a note or a message often drags along an invisible space at the end.
4. Autocorrect substitution. Notes apps turn ' into a curly quote and may add accents. The character now looks right and is a different character.
5. Router truncation. If the password is long or contains quotes or backslashes, re-open the router panel and re-enter it — what was saved may not be what you submitted.

If you get this far, the pragmatic fix is to generate a clean password from the safe set and set it once. See also our WiFi security guide for the other router settings worth changing while you are in there.

The bottom line

The specification is generous — 8 to 63 printable ASCII characters — but the useful answer is narrower. Use letters, digits and the symbols ! @ # $ % ^ & * _ + - =, skip quotes, backslashes, backticks, semicolons, commas and spaces, drop look-alike characters, and never go outside ASCII. Then buy your security with length rather than exotic punctuation: 16–20 characters from the safe set is stronger than 12 characters of unusual symbols, and it will actually work on every device you own. Curious how much length really buys you? See how long it takes to crack a password.

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