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Preview of randumb — coherent fake data form filler

randumb — coherent fake data form filler by vøiddo

Form filler with 58 locales and country-coherent identities (Germany→Hans Müller→München→€). Bulk CSV for test DBs. Free.

Available on Firefox for Android™Available on Firefox for Android™
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Extension Metadata

Screenshots
a German signup form filled with a coherent local identity (Hans Müller, München, +49, EUR — money shot, whole value prop in one image)popup with locale picker + marketing framingpost-install welcomesettings page
About this extension
randumb is a form-filler for developers, QA engineers, and product
testers. Press Alt+Shift+F (or click the floating "r̸ fill form" badge)
and every fillable field on the page gets a coherent fake identity:
matching first name, last name, email, phone, street, city, postal
code, and currency — all from the same country.

The difference from every other form filler: coherence. Most tools pick
each field independently and produce things like "Germany, John Smith,
Tokyo, $12.50". randumb picks a country first, then draws everything
from that country's dictionary. You get "Deutschland, Hans Müller,
München, €7.423,00" — the kind of data your localization tests expect.

WHAT IT FILLS

• full name / first name / last name / middle name
• email (with realistic provider per country — gmx.de for Germany,
libero.it for Italy, gmail.com for the US, etc.)
• phone with country-correct format
• street / city / region / postal code
• company name / job title
• username / password (passes basic complexity)
• birthdate in a reasonable adult range
• Luhn-valid test credit card numbers (structurally valid, never real
stolen numbers)
• 30+ other field kinds, detected from field name, id, label,
placeholder, and autocomplete attribute

HOW IT DETECTS FIELDS

Every input is scored against a token table with weights for:

• input type (email, tel, password)
• HTML5 autocomplete attribute (given-name, street-address, …)
• name / id / placeholder / label / aria-label tokens

Fields the classifier is confident about get the matching generator;
fields it isn't get a generic string. All fills go through a native-
setter + input/change/blur event dispatch so React/Vue/Angular forms
correctly pick up the change.

LOCALES

Free: 15 locales — US, UK, DE, FR, ES, IT, PT, PL, TR, NL, SE, NO,
DK, FI, JP.

Pro adds 43 more, including Israel, UAE, Saudi Arabia, India, China,
Korea, Indonesia, Vietnam, Thailand, Brazil, Argentina, Mexico, and
31 others. Each locale has its own first-name / last-name dictionary,
currency, phone format, and city list.

PRO — $4.99/mo

• All 58 locales
• Bulk CSV export (up to 1,000 rows per click — great for seeding
test databases)
• Seeded mode: same seed → same output (reproducible fixtures)
• Per-domain presets: signup.acme.com always fills US, dev.myapp.local
always fills DE
• Custom field mappings: force field "user_code" to always fill as
an email, for example

Team ($9/seat) and Enterprise ($49 flat) at voiddo.com/tools/randumb/upgrade.

PRIVACY

randumb writes generated data INTO fields on the page you triggered
it on. It does not read what was there before, does not transmit form
values anywhere, does not inspect pages you didn't invoke it on. The
only outbound request is license validation (only if you've entered a
Pro key), at activation and once per 24h.

Full policy: https://voiddo.com/tools/randumb/privacy/
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Permissions and data

Required permissions:

  • Download files and read and modify the browser’s download history
  • Access your data for all websites

Optional permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
Learn more
More information
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Version
1.0.3
Size
130.81 KB
Last updated
6 days ago (Apr 28, 2026)
Related Categories
  • Web Development
License
Mozilla Public License 2.0
Privacy Policy
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