Data Tinker: Test Data Generator & Form Filler

Data Tinker gives you valid test data while you test a form: identifiers that pass the same checks a real one does, in a sidebar next to the page. Drag a value into a field, or fill in the whole form with one click.

Everything is generated in your browser. There is no account, no server and nothing leaves your machine.

DATA THAT PASSES VALIDATION

Every generator computes the check digit or the format the real thing has, and the tests run against examples published by the issuing bodies — not against the generator agreeing with itself.

• Identity documents, tax numbers and bank accounts from Australia, Austria, Belgium, Brazil, Canada, Finland, France, Germany, Italy, Mexico, the Netherlands, Norway, Poland, Portugal, Spain, Sweden, Switzerland, the United Kingdom and the United States, plus VAT numbers from across Europe. • Across 70 countries: passports with their machine-readable lines, phone numbers and postal codes in each country's format, and the IBAN of most of those that use one. • Everyday form data: test card numbers, phone numbers, emails, addresses, dates and passwords, product barcodes and book numbers, and technical values for developers. • Whole profiles — a person, with age, job title and salary, or a company — where the city, the region and the postal code belong together. Pick the country once, and the form fill, your rules and the right-click menu follow it. • Many at once: a table of up to 10,000 profiles with the columns you choose — an ID counter, or one built from the others, like an email from the name — as CSV, JSON, XML or SQL INSERT statements. Or "All in one": a value from every generator on a single screen.

Test data that is safe to use: cards are the test numbers payment gateways publish for exactly this, and no bank issues; phone numbers come, where the country has one, from the range its regulator reserves for fiction.

FILL IN THE WHOLE FORM

• One button, a right-click or Alt+Shift+D. Data Tinker recognizes each field by its autocomplete hint, its name, its label and its type — and when nothing else says what it wants, by the format it asks for — and types into it the way a person does, so React forms and masked date fields keep the value. • Time, week, month, color and range fields too, within their limits. If you build the form, a data-tinker attribute says what a field is, or that it is off limits. • It leaves alone what you cannot see — the hidden fields that catch bots. • Then it shows a report: what went into each field, which ones need a look, and which required ones got nothing. Copy it into a ticket as a table, or as JSON. • A small icon next to the focused field fills it with one click (with Shift, the whole form). You can switch it off, or limit it to some sites.

MAKE IT YOURS

• Rules: "if the field mentions these words, put this in it" — a generator, a fixed value, a number of N digits, a date between two years, one of a list, or a pattern like ###-@@@ for your own reference numbers. • Templates: detect a form's fields, or capture the values it has right now, and paste them into another form — also inside an iframe. A template can hold several data sets (an individual, a company) and fill a page on its own as soon as it opens, and three of them can have a keyboard shortcut. • Projects: group your rules and templates by application, each with the sites it belongs to. • Back up everything to a file and restore it in another browser. Templates that arrive from a file never fill a page on their own until you switch that on.

FIND THE EDGES

• Boundary values with the reason each one is there: very long text, Unicode that breaks counters, injection strings, extreme numbers, odd emails and dates. • "Test the form's limits" tries them field by field and tells you what the form accepted, what it cut and what it rejected — including the limits a page only states in its error messages.

PRIVACY

Data Tinker asks for access to all sites so it can fill a form on whichever page you are testing, and show its icon there. It reads a page's form only when you ask it to — fill, detect, capture or test the limits — and only in your browser. Password fields are never captured. What you create is stored locally and never sent anywhere. Firefox lets you withdraw that access in the add-on's permissions; Settings in the sidebar then says so, with a button to give it back.

The toolbar button opens and closes the sidebar. Keyboard shortcuts are changed in Add-ons › ⚙ › Manage Extension Shortcuts. It needs Firefox 140 or later, on desktop.

Interface in Dutch, English (US and UK), French, German (Germany and Switzerland), Italian, Norwegian, Polish, Portuguese (Portugal and Brazil), Spanish (Spain and Mexico) and Swedish.