Formseed: Realistic Test Data & Form Filler for Developers

Fill any form with realistic, matching test data in one click. Works with React and Vue. Runs entirely on your own machine.

Formseed fills the form you are looking at with realistic test data, so you can see how your UI behaves with real-looking content instead of typing "asdf" into twelve fields again. It reads the page the way a person does — the visible label, the placeholder, the column header above a table cell, the text next to the input — not just the "name" attribute, which real applications minify into things like f_12 or ctl00$ContentPlaceHolder1$tb0. That is why it works on applications that other form fillers give up on. WHAT MAKES THE DATA USEFUL The values in one record agree with each other. The email is built from the name. The city belongs to the state, and the ZIP and the phone's area code match the city. Dropdowns agree too — a State select lands on the state of the city Formseed just wrote, not a random one. Independently random fields look obviously fake and test nothing. No "John Doe", no "test@test.com", no Lorem Ipsum, unless you ask for placeholders explicitly. EDGE CASES Switch to Edge cases to find layout breakage before your users do: very long names with apostrophes and non-Latin scripts, very long addresses, boundary numbers, boundary dates, and empty optional fields. IT STAYS ON YOUR MACHINE Formseed makes no network requests. None. The page you are on is never uploaded, logged, or sent anywhere, which means you can use it on your company's internal admin panel without thinking about it. It asks for no host permissions, so Chrome never shows you the "read and change all your data on all websites" warning. Nothing runs on any page until you click the button, and access ends when you navigate away. IT STAYS OUT OF YOUR WAY • Never submits your form, clicks a button, or navigates anywhere • Never touches password, payment-card, or one-time-code fields • Never overwrites something you typed, unless you turn that on • Only ever picks options a dropdown already has • Tells you what it skipped and why — nothing is dropped silently • One click to clear everything it filled WORKS WITH MODERN FRAMEWORKS Controlled React and Vue inputs keep their value in component state, so a filler that only writes to the DOM appears to work and then vanishes on the next render. Formseed updates the framework's own state — verified against React and Vue, with tests that fail if the mechanism ever stops working. KNOWN LIMITATION Fields inside frames from another domain — payment card fields, some embedded form widgets — cannot be filled. That is the direct cost of asking for no host permissions, and those fields are listed as skipped rather than quietly ignored. Free. No account. No telemetry.