Generated data

Data language

Choose English, Français or العربية for generated names, addresses and text in Options → Generator. Labels are always recognized in all three languages, whatever you pick.

Fill settings

Open the settings button at the top of the options page:

Setting	Default	What it does
Replace existing values	On	Fills fields that already have a value. Turn it off to keep what's there.
Fill unknown fields	On	Fills fields DevFiller doesn't recognize with readable words or sentences, even if the site's own validation might reject them.
Learned guesses	On	When the rules aren't sure what a field is, a small model built into the extension suggests a type. It runs offline, and the side panel marks its guesses.
Generate test passwords	Off	Fills password fields. The password and its confirmation get the same value.
Addresses and phones	Mixed	Where cities, postal codes, districts, countries and phone numbers come from: United States, France or Algeria, or Mixed to pick one of them for each fill.
Repeatable data	Empty	Type a seed, such as checkout-test, to get exactly the same values on every fill. Leave it empty for fresh data on every click.

Repeatable data

With a seed, the same form gets the same identity and the same values every time: generic text, numbers, dates, choices and phone numbers included. Use it for tests that compare screenshots or expect known values. Change the seed to get a different, equally repeatable set.

• Each field draws from its own stream, so adding a field to the form doesn't change the others.
• Dates don't depend on the day you run the test: birth dates count back from 1 January 2026, and start dates fall in 2030.
• Seeded fills don't use AI suggestions, since those can't be repeated.
• A field whose name and ID are generated anew on each page load (such as :r1: in React apps) can't be matched from one run to the next, so it gets a new value. So can a field whose page sets its limits relative to today.

What the data looks like

• Names are real names. Jamie, Parker and Jamie Parker, with the username jamie.parker and the email jamie.parker@example.com. Each fill picks a different identity when one is available.
• No random strings. Unknown text fields get simple words such as "Garden" or "River"; text areas get short sentences.
• Safe by design. Emails and websites use example.com. US phone numbers use the fictional range 202-555-01xx.
• Places that fit together. The city, postal code, district, state or wilaya, country, nationality and phone number all come from the same country. With Algeria, you get one of about 1,500 real communes with its daira and wilaya (for example Bab El Oued, daira of Bab El Oued, Alger), the wilaya's main postal code (16000), a +213 mobile number and Algerian names, in Arabic script when the data language is Arabic. DevFiller knows the 69 wilayas of Law 26-06 of 4 April 2026, including the eleven new ones.
• Phones follow the form. When the form asks for a country, or the phone field shows a dial code such as +213 or +33, the number is written in that country's format. French and Algerian numbers follow the real format and may be in use, so never use them to send messages.
• Numbers where numbers belong. Lengths, weights and other measurements are sized for their unit (Épaisseur (mm) gets a few millimetres, Longueur (mm) a few thousand). Order, invoice and part numbers look like real references (CMD-2030-0421). Fields that ask for digits get digits.
• Within the field's rules. Numbers respect min, max and step; dates respect their range; dropdowns and radio buttons get a real option, different from the last one when possible.

The pools are finite, so values repeat over time, and a website's own validation may still reject a value.

See Field types for the full list of recognized fields and labels.