OttoFill

Otto remembers every form you fill and fills new ones for you — privately, on your device.

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.