Typos in email addresses: the silent signup killer
A mistyped address means a lost customer who never knows why they didn't get your email. Here is how common typos are and how to catch them.
Photo by Firmbee on Pixabay
Someone signs up, waits for the confirmation email, never gets it, assumes your product is broken and leaves. They typed maria@gmial.com. You never find out.
What typos look like
Most mistakes fall into a few patterns:
- Transposed letters:
gmial.com,hotmial.com - Missing letters:
gmai.com,yaho.com - Wrong ending:
gmail.con,gmail.cm,gmail.co - Extra or missing dots:
gmail..com,gmailcom - Mobile autocorrect turning a name into a "word"
All of these produce an address that is well formed, so a simple format check lets them through.
Why they cost more than you think
- A lost signup. The person can't confirm and doesn't come back.
- A bounce. Or worse, a delivery to a typo-trap domain.
- A privacy problem. If the typo domain is real and someone owns it, they receive someone else's email.
How to catch them
Compare against popular domains. The most common typos are of a short list of big providers. Measure the edit distance between the typed domain and each popular one. If it is within one or two edits, suggest the correction.
Ask the user, don't decide for them. Show "Did you mean maria@gmail.com?" with a one-click accept. Silent auto-correction is risky: you may fix an address that was actually right.
Be careful about false alarms. Many legitimate domains are close to popular ones. hotmail.co.za is not a typo of hotmail.com. A good checker needs a list of legitimate lookalikes to leave alone, or it will annoy real customers.
What Mailsure does
Every response includes a suggestion field when a domain looks like a typo of a popular one, and the result is marked risky so you can decide what to do. In the API:
{
"status": "risky",
"reason": "possible_typo",
"suggestion": "maria@gmail.com"
}
Show the suggestion in your form, and let the user confirm.
The cheapest fix in email
Typo correction at the form takes minutes to add and recovers signups you would otherwise lose silently. Pair it with a real-time API check and your confirmation emails start arriving.
