The MockFill alternative for testers who need control
MockFill generates realistic test data in one click. Fillr does that too — and then lets you save forms as presets, set a rule for every field, and fill from your own test data, row by row.
MockFill is a clean, private, one-click generator: click it, and every field gets context-aware realistic data — names, emails, addresses, phones. For a quick smoke-fill, it's a tidy choice.
But if you're looking for an alternative, it's usually because generated-and-go isn't enough. MockFill regenerates fresh data every time, with no saved per-form setup and no way to fill from your own data. The moment the values matter — the same controlled setup every run, your own test rows, locale-correct data — generating random values runs out.
Fillr was built for exactly that. Here's an honest, feature-by-feature comparison.
- How it fills
- One-click generated data
- Per-form presets
- No
- Fill with your own data
- Not available
- Languages
- Not specified
Facts checked June 2026. Tell us if something changed and we’ll update it.
Fillr vs MockFill
| Capability | MockFill | Fillr |
|---|---|---|
| One-click whole-form fill with realistic data | Yes | Yes — free |
| Smart field detection | Yes | Yes |
| Data types | Names, emails, addresses, phones, dates | 100+ types, free |
| Custom validation rules | Yes — set up manually | Yes |
| Save a form as a reusable preset | No | Yes — unlimited, free |
| Per-field fill rules on a specific form | No | Generate · Fixed value · Blank · Skip · Dataset column |
| Fill with your own data (CSV / Excel / JSON) | No | Yes — row by row, with a “row 3 of 20” readout (Pro) |
| Build, edit and export test datasets | No | Yes |
| Preset auto-matches the page you're on | No | Yes — URL patterns |
| Languages | Not specified | 60+ locales (Pro) |
| Runs locally / private | Yes | Yes |
Where MockFill stops
Credit where due: as of its March 2026 update, MockFill (826 users on the Chrome Web Store, 5.0★ from 5 ratings) is a clean, focused tool — one-click autofill, smart field detection, context-aware values, custom validation rules, and a privacy-first design that runs entirely in your browser with no external API calls. For a quick "does this form accept valid input?" check, it gets you there.
But its model is generate-and-go. It regenerates fresh values on every click, with no saved per-form profile — so you re-decide behavior on each visit, and you can't replay the same controlled setup tomorrow. There's no way to fill from your own data (no CSV, Excel or JSON import), no concept of rows or a reproducible run, and no listed locale options, so data is effectively one language. Custom validation rules exist, but you set them up manually rather than saving fill behavior per field on a form you reuse.
None of this makes MockFill useless — generated fill is genuinely enough for some work. It makes it incomplete for testers whose test data matters.
What Fillr does differently
Capture once, fill forever. Point Fillr at any form and save it as a preset. Every field gets a rule: Generate realistic data, use a Fixed value, leave it Blank, Skip it, or pull it from a column of your own dataset. Land on that page again and the right preset surfaces by itself — one click, the same controlled setup every time.
Your data, not just plausible data. Import a CSV, Excel or JSON file as a dataset, map its columns to the form's fields, and fill row by row — sequentially for reproducible runs (the extension tells you “row 3 of 20”), or randomly for variety. When a bug appears, you know exactly which row produced it.
Realistic in 60+ languages. 100+ data types — names, emails, addresses, phones, IBANs and more — generated locale-aware, from English to Japanese. i18n testing stops being a special case. Like MockFill, filling happens locally in your browser and your data stays private.
Switching takes about two minutes
Install Fillr, open any form, and click Fill — one-click fill with all 100+ data types is free, so the MockFill workflow you already have keeps working.
Then do the thing MockFill can't: hit Save on a form you test often, set a rule for each field, and you have your first preset that loads itself across dev, staging and prod. The free plan includes unlimited presets and three datasets of 50 rows — own-data filling, every locale, and unlimited datasets come with Pro ($6.99/mo or $69/yr, 7-day trial).
Questions, answered.
Fill your next form with data you control
Free forever for everyday filling — unlimited presets, all 100+ data types.
Add Fillr to Chrome