extension compare · developer / qa · 2026

Best random form filler extensions 2026

randumb vs Fake Filler vs Mockaroo — locale-coherent fake data generation for testing, QA and demos, compared honestly.

updated may 2026 · no paid placements · vøiddo makes randumb

why locale-coherence matters for fake data

  • Form validation often rejects a French postcode paired with a German phone format — incoherent data produces false test failures.
  • Staging environments with mixed-locale data skew analytics dashboards, making country-level reports meaningless.
  • Demo screenshots with "John Smith" at "12 Rue de la Paix, Lyon" look broken and erode client trust immediately.
  • randumb keeps every identity field in the same country — name, surname, street format, postcode, phone prefix and email domain all match.
free · chrome only
Fake Filler

the most popular random form filler extension for Chrome. fills fields with random data, but does not enforce locale coherence across identity fields.

  • popular — large install base
  • right-click + keyboard shortcut fill
  • custom field rules via regex
  • Chrome only — no Firefox or Edge
  • locale fields can mismatch (US name, UK postcode)
  • no bulk CSV export
  • no multi-locale toggle panel
freemium · web app
Mockaroo

a web-based fake data generator with a broad field-type library. no browser extension — you generate and download data outside the browser, then paste it in.

  • many field types (50+) including custom formats
  • CSV / JSON / SQL / Excel export
  • API access for automated test seeding
  • web app only — no right-click to fill
  • requires leaving the page you are testing
  • free tier limited to 1,000 rows/download
  • no locale-coherent identity bundles
web app · no extension
Random User Generator

a free API and web interface that generates random user data with nationality support. useful for seeding databases, but requires leaving the form or writing API code.

  • nationality filter — some locale awareness
  • free API with generous rate limit
  • JSON / CSV output for code integration
  • no browser extension — cannot fill forms directly
  • must write code or copy-paste manually
  • limited to ~60 nationalities without custom config
  • no right-click workflow

feature comparison

key differences between randumb and the main alternatives.

feature randumb Fake Filler Mockaroo Random User
locale-coherent identities all fields match can mismatch ~ per field only ~ nationality only
right-click to fill web app web app / API
number of locales 58 ~20 partial 50+ via fields ~60 via API
Firefox support N/A N/A
Edge support N/A N/A
bulk CSV export up to 1,000 rows paid tiers via API
works offline no network calls requires internet requires API
no account required ~ free tier ok
postcode format by locale generic ~ per field
phone format by locale ~ limited per field
pricing free free free / paid free
where available Chrome + Firefox + Edge Chrome only web app web / API

use-case verdicts

QA & form testing
randumb

right-click fill keeps you in the page. locale-coherent data avoids false validation failures. works on Chrome, Firefox and Edge — wherever your QA browser is.

seeding test databases
randumb or Mockaroo

if you need bulk rows for a DB seed script, randumb's CSV export (up to 1,000 rows, coherent locale) is faster to reach. Mockaroo wins if you need custom field types beyond names and addresses.

demo & staging screenshots
randumb

screenshots need identities that look real. a French demo with a German phone and a UK postcode looks broken. randumb generates coherent personas that read correctly at a glance.

frequently asked questions

install randumb free

58 locales. country-coherent. right-click.

form filler that keeps names, addresses, postcodes and phone numbers in the same country. free on all three major browsers.

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