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Preview of OttoFill

OttoFill by BalaK

Private autofill that learns from you. Remembers every form you fill and fills the next one — on your device. Works offline.

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About this extension
Otto remembers every form you fill. And fills the next one for you.

A privacy-first browser extension that learns your data, keeps it encrypted on your device, and recognises fields on sites it has never seen — using on-device AI. Works offline. Your data never leaves your machine for the free features.

Learns once. Recognises everywhere.
- Otto learns — when you submit a form, Otto quietly remembers each field, including the corrections you make, and keeps it encrypted on your device.
- Otto recognises — on any new form, a four-tier engine matches each field: exact recall, deterministic rules, on-device AI, then an optional LLM.
- You fill — click a teal chip to fill one field, or "Fill all" for the whole form. Hover any chip to see exactly why Otto filled it.

The four tiers
- Tier 0 — Exact recall (free, local): reuses the exact value you filled on this form before.
- Tier 1 — Deterministic (free, local): rule-based label, name & autocomplete matching.
- Tier 2 — On-device AI (free, local): local embeddings match "e-mail address" to your stored email — offline, no network.
- Tier 3 — LLM fallback (Pro / BYO): resolves the fields nothing else can — via a privacy proxy or your own key.

Everything you need. Nothing you don't.
- Capture on submit — learns from every form you submit, including your edits.
- Inline fill chips — a teal chip on each recognised field; hover for provenance.
- On-device AI matching — local embeddings (Transformers.js, WASM) with no network call.
- Knowledge base manager — search, edit and merge everything Otto knows.
- CSV & text import — import a label,value CSV, or paste freeform notes.
- Zero-knowledge sync — encrypt your knowledge base with a passphrase and sync across devices; the server only ever sees ciphertext.

Your data lives on your device. Full stop.
Encrypted locally · Works offline · No tracking, no telemetry · Zero-knowledge sync · No account needed for the free features. The one exception: optional Tier-3 AI runs only when you click the sparkle on a field.
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Permissions and data

Required permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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Version
0.1.5
Size
5.89 MB
Last updated
13 hours ago (Jun 21, 2026)
Related Categories
  • Privacy & Security
License
All Rights Reserved
Version History
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