Trustevo / Products / PII Guardrail

Use AI freely. Never expose what matters.

On-device detection masks sensitive data before it reaches any AI assistant — then restores originals in the response. Nothing leaves your browser.

Works on Claude · ChatGPT · Gemini · Perplexity · GitHub Copilot

chatgpt.com — intercepted by PII Guardrail
$ intercepting prompts
How it works

Three steps. Zero configuration.

01

Detect

An on-device GLiNER model scans every prompt before you hit send. Cards, SSNs, emails, phone numbers, names — all caught locally, no server involved.

before sendMy SSN is 532-83-2948
02

Mask

Each value is replaced with a format-preserving surrogate. The AI sees a realistic placeholder — preserving context without the real data.

sent to AIMy SSN is [SSN_a3f2]
03

Restore

When the response streams back, surrogates are swapped for originals. You read real data. The AI never saw it.

you seeSSN 532-83-2948 is valid.
Provable, not promised

You don't have to take our word for it.

Most privacy tools ask you to trust a server — even a “local” proxy is a place your data flows to. PII Guardrail runs detection in your browser, so there's nothing to trust. And you can verify it three ways.

📡

See everything it sends

The extension's popup shows a live ledger of its only two outbound requests — the one-time detection model and (if you opt in) PII-free usage counts. Your detected data: 0 bytes, always.

🔒

Your browser enforces it

A Content Security Policy of connect-src 'self' means the browser physically blocks the extension from connecting to your AI provider with raw data. Not a policy — a platform guarantee.

🔍

Check it yourself

Open your browser's Network tab, send a prompt, and look: your data isn't in any request. The installed extension's manifest, the model, and the license verification key are all yours to inspect — no trust required. Read the full security architecture →

Enforcedconnect-src 'self' models.trustevo.ai
Reversible by design

Most tools redact. We mask — and give it back.

One-way redaction destroys your data: the model sees ███ and you lose context. PII Guardrail swaps in a realistic, format-preserving surrogate, then restores the real value in the response — so the AI reasons correctly and you read your actual data.

One-way redaction

Other tools blank the value out. The model loses the shape and meaning, answers worse, and the original is gone for good.

typical redactionCharge card ████ — gone
vs

Reversible surrogate

A format-preserving token keeps the data’s shape, so the AI still understands it’s a card — and the vault restores the real number in the answer.

sent → restored[PAN_7c1d]4111 1111 …
+

Consistent & on-device

The same value always maps to the same surrogate within a session, so the model’s reasoning about “the same person” holds. The value↔token map lives only in your browser’s memory and is wiped when the tab closes — never persisted.

Why PII Guardrail

Built for teams that handle sensitive data.

Zero egress — enforced by the platform

Detection, masking, and restoration run entirely in your browser. The extension's Content Security Policy sets connect-src 'self' — even if a dependency tried to phone home, the browser blocks it at the platform level. Not a policy. A technical guarantee.

CSPconnect-src 'self' models.trustevo.ai
🧠

On-device model

GLiNER small v2.1 — loaded once from our CDN, cached locally. No API calls on the detection path. Works offline after first load.

🎯

Format-preserving tokens

Surrogates like [PAN_7c1d] preserve structure. The AI understands the data shape and gives useful answers.

🏛️

Compliance-ready

Helps keep AI usage aligned with GDPR, HIPAA, and CCPA by stopping PII at the source — before it reaches any third-party model.

Detection coverage

Three tiers of protection.

Free covers Tier 1. Pro and Team unlock all tiers.

T1Payment cards4111 1111 ···
T1Social security532-83-···
T1IBAN / bankGB29 ···
T2Email addressj··@···.com
T2Phone number+1 (···) ···
T3Person nameJ·· S···
See all tiers in pricing →
Get started today

Free forever for Tier 1.
Pro unlocks everything.

No card required for the free plan. Install the extension and your data stays yours.

We use privacy-respecting analytics to understand how visitors use this site. No data is shared with AI providers and you can decline at any time.