How many fields should a contact form have?
Every extra field means fewer people fill the form in. Too few fields, though, and you get messages you can't act on. Here is how to find the balance.
The more fields a form has, the fewer people send it. That's true, but cutting the form down to two fields doesn't solve anything.
A form that only asks for a name and a message brings you things like "Hello, can I get a price?" You need to ask three more questions before you can reply, and the back and forth takes three days.
Can I write a first reply without this field?
That's the question I ask about every field. If you couldn't write a useful first reply without a piece of information, add the field. If you could, leave it out.
For web design enquiries my form has five fields: name, email, what they want built, their current site if they have one, and a budget range.
Does asking for budget scare people off?
As a free-text field, it does. People hesitate to type a number. As a range to pick from, it doesn't.
Offer options like "$300-500", "$500-1,000", "over $1,000" and "not sure yet". Keep that last one. People who don't know their budget still send the form, and people who do know tell you up front.
Keep required fields few
You can ask for five fields and only require three. Ask for a phone number but don't make it required. Plenty of people prefer email, and losing them over a phone field isn't worth it.
Mark required fields with an asterisk and say at the top of the form that starred fields are required.
Error messages
Everyone has run into the worst form behaviour. You press send, the page reloads, everything you typed is gone and there's a red warning at the top.
Show the error right under the field, keep what was typed, and move focus to the first field with a problem. The message should say what to do. Write "the email address seems to be missing an @" instead of "invalid".
After submitting
"Your message was sent" isn't enough. People want to know whether it arrived, when they'll hear back, and what to do if they typed something wrong.
Show a clear confirmation on screen and send an automatic email at the same time. The email shows the message arrived and leaves them an address they can reply to.
Bot protection should be invisible
Making visitors solve puzzles like "select the squares with traffic lights" wears out real customers. Invisible methods work better. You can add a hidden field that people never see but bots fill in, measure the time between opening the form and submitting it, or limit how many submissions come from one IP.
The form on this site works that way. Real visitors don't notice anything, and bots can't get a message through.