Blindfold JS SDK

Detect, redact, tokenize, and mask PII in JavaScript/TypeScript. 80+ entity types, 30+ countries, works offline with zero dependencies.

Why Blindfold?

• Works offline, zero dependencies — No API key needed for local detection. No network calls. No external packages.
• 80+ PII entity types across 30+ countries with checksum validation (Luhn, IBAN mod-97, Verhoeff, etc.)
• 85x faster than Presidio — 0.4s vs 34s on 3,000 samples (benchmark)
• Higher accuracy — F1 58.6% vs Presidio 38.8% on AI4Privacy multilingual benchmark
• 8 operations: detect, redact, tokenize, detokenize, mask, hash, encrypt, synthesize
• Compliance-ready — Built-in GDPR, HIPAA, PCI-DSS policies
• Optional NLP upgrade — Add API key to detect names, addresses, organizations (60+ additional entities)
• Batch processing, typed errors, full TypeScript support

Quick Comparison

| Feature | Blindfold | Presidio | regex-only | |---|---|---|---| | Entity types (local) | 80+ | ~20 | Custom | | Countries | 30+ | ~5 | Custom | | Checksum validation | Luhn, mod-97, Verhoeff, ... | Partial | No | | Speed (3K samples) | 0.4s | 34s | Varies | | Zero dependencies | Yes | No (spaCy) | Yes | | NLP upgrade path | Yes (API) | Yes (built-in) | No | | Tokenize/detokenize | Yes | No | No |

Common Use Cases

• Sanitize LLM prompts — Strip PII before sending to OpenAI, Anthropic, etc.
• PII-safe RAG pipelines — Redact before embedding, restore after retrieval
• Log scrubbing — Anonymize data in logs and data pipelines
• GDPR/HIPAA compliance — Built-in policies for AI applications
• Synthetic test data — Format-preserving fake data generation

Install

npm install @blindfold/sdk
# or
yarn add @blindfold/sdk
# or
pnpm add @blindfold/sdk

Quick Start (no API key needed)

import { Blindfold } from '@blindfold/sdk'

const client = new Blindfold()

// Detect PII locally — no API key, no network call
const result = await client.detect("Email [email protected], SSN 123-45-6789")
for (const entity of result.detected_entities) {
  console.log(`${entity.type}: ${entity.text} (score: ${entity.score})`)
}
// Email Address: [email protected] (score: 0.95)
// Social Security Number: 123-45-6789 (score: 1.0)

// Redact PII locally
const redacted = await client.redact("Email [email protected], SSN 123-45-6789")
console.log(redacted.text)
// "Email, SSN"

Protect AI Prompts

Tokenize PII before sending to any LLM. The AI never sees real data.

OpenAI

import { Blindfold } from '@blindfold/sdk'
import OpenAI from 'openai'

const bf = new Blindfold() // Free local mode
const openai = new OpenAI()

// 1. Tokenize PII
const safe = await bf.tokenize("My name is John Smith, email [email protected]")
// safe.text → "My name is <Person_1>, email <Email Address_1>"

// 2. Send to GPT — PII never reaches OpenAI
const response = await openai.chat.completions.create({
  model: 'gpt-4o',
  messages: [{ role: 'user', content: safe.text }]
})

// 3. Restore original data
const result = bf.detokenize(response.choices[0].message.content, safe.mapping)
console.log(result.text)

Anthropic Claude

import { Blindfold } from '@blindfold/sdk'
import Anthropic from '@anthropic-ai/sdk'

const bf = new Blindfold()
const anthropic = new Anthropic()

const safe = await bf.tokenize("My name is John Smith, email [email protected]")

const response = await anthropic.messages.create({
  model: 'claude-sonnet-4-20250514',
  max_tokens: 1024,
  messages: [{ role: 'user', content: safe.text }]
})

const result = bf.detokenize(response.content[0].text, safe.mapping)
console.log(result.text)

Works with any AI provider: OpenAI, Anthropic Claude, Google Gemini, AWS Bedrock, Azure OpenAI, LangChain, LlamaIndex, Vercel AI SDK, CrewAI — see all integrations.

Upgrade to Blindfold API (optional)

For names, addresses, organizations, and 60+ entity types, add your API key:

1. Sign up at blindfold.dev
2. Get your API key at app.blindfold.dev/api-keys
3. Set environment variable: BLINDFOLD_API_KEY=sk-***

// With API key — auto-switches to NLP-powered API
const client = new Blindfold({ apiKey: 'sk-...' })
const result = await client.detect("John Smith lives at 123 Oak Street")

Initialization

import { Blindfold } from '@blindfold/sdk'

// Local mode (no API key) — regex-based detection
const client = new Blindfold()

// API mode (with API key) — NLP-powered detection
const client = new Blindfold({ apiKey: 'sk-...' })

// Force local mode even with an API key (useful for latency-critical paths)
const client = new Blindfold({ apiKey: 'sk-...', mode: 'local' })

Operations

Tokenize (Reversible)

Replace sensitive data with reversible tokens (e.g., <Person_1>).

const response = await client.tokenize(
  "Contact John Doe at [email protected]",
  {
    policy: 'gdpr_eu',  // Optional: 'hipaa_us', 'basic', 'pci_dss', 'strict'
    entities: ['person', 'email address'],  // Optional: filter entities
    score_threshold: 0.4  // Optional: confidence threshold
  }
)

console.log(response.text)
// "Contact <Person_1> at <Email Address_1>"

console.log(response.mapping)
// { "<Person_1>": "John Doe", "<Email Address_1>": "[email protected]" }

Detokenize

Restore original values from tokens. Runs client-side — no API call.

// No await needed — runs locally!
const original = client.detokenize(
  "AI response for <Person_1>",
  response.mapping
)
console.log(original.text)
// "AI response for John Doe"

Redact

Permanently remove sensitive data.

const response = await client.redact(
  "My password is secret123",
  { entities: ['person', 'email address'] }
)

Mask

Partially hide sensitive data (e.g., ****-****-****-1234).

const response = await client.mask(
  "Credit card: 4532-7562-9102-3456",
  { masking_char: '*', chars_to_show: 4, from_end: true }
)
console.log(response.text)
// "Credit card: ***************3456"

Hash

Replace data with deterministic hashes (useful for analytics/matching).

const response = await client.hash(
  "User ID: 12345",
  { hash_type: 'sha256', hash_prefix: 'ID_' }
)

Encrypt

Encrypt sensitive data using AES (reversible with key).

const response = await client.encrypt(
  "Secret message",
  { encryption_key: 'your-secure-key-min-16-chars' }
)

Synthesize

Replace real data with realistic fake data. Works offline with format-preserving generation.

// Works offline — no API key required
const client = new Blindfold()
const response = await client.synthesize("Email [email protected], SSN 123-45-6789")
console.log(response.text)
// "Email [email protected], SSN 847-29-3156"

// With API key — NLP-powered synthesis (names, addresses, etc.)
const response = await client.synthesize(
  "John lives in New York",
  { language: 'en' }
)
console.log(response.text)
// "Michael lives in Boston"

Batch Processing

Process multiple texts in a single request (max 100 texts):

const result = await client.tokenizeBatch(
  ["Contact John Doe", "[email protected]", "No PII here"],
  { policy: "gdpr_eu" }
)

console.log(result.total)      // 3
console.log(result.succeeded)  // 3
console.log(result.failed)     // 0

result.results.forEach(item => console.log(item.text))

All methods have batch variants: tokenizeBatch, detectBatch, redactBatch, maskBatch, synthesizeBatch, hashBatch, encryptBatch.

Local PII Scanner

The built-in regex scanner works offline with zero dependencies. Use it directly for fine-grained control:

import { PIIScanner, EntityType } from '@blindfold/sdk/regex'

// Default: US locale
const scanner = new PIIScanner()
const matches = scanner.detect("Call me at [email protected] or 555-867-5309")

for (const match of matches) {
  console.log(`${match.entityType}: ${match.text} (score: ${match.score})`)
}

// Redact PII
const { text, matches: redacted } = scanner.redact("SSN 123-45-6789, CC 4532015112830366")
console.log(text)
// "SSN, CC"

Multi-locale support

// US + EU entities
const scanner = new PIIScanner({ locales: ['us', 'eu'] })
const matches = scanner.detect("SSN 123-45-6789, IBAN DE89370400440532013000")

// UK entities
const scanner = new PIIScanner({ locales: ['uk'] })
const matches = scanner.detect("NI number: AB 12 34 56 A")

// All locales
const scanner = new PIIScanner({ locales: ['us', 'eu', 'uk'] })

Filter by entity type

// Only detect emails and credit cards
const scanner = new PIIScanner({ entities: [EntityType.EMAIL, EntityType.CREDIT_CARD] })

Error Handling

import { AuthenticationError, APIError, NetworkError } from '@blindfold/sdk'

try {
  await client.tokenize("...")
} catch (error) {
  if (error instanceof AuthenticationError) {
    // Handle invalid API key
  } else if (error instanceof APIError) {
    // Handle API error (e.g. validation)
  } else if (error instanceof NetworkError) {
    // Handle network issues
  }
}

| Entity Type | Locale | Validation | |---|---|---| | Email Address | Universal | RFC 5322 pattern | | Credit Card Number | Universal | Luhn checksum | | Phone Number | Universal | Format + digit count | | IP Address (v4/v6) | Universal | Octet range | | URL | Universal | TLD validation | | MAC Address | Universal | Pattern | | Date of Birth | Universal | Context-required | | CVV/CVC | Universal | Context-required | | Social Security Number | US | Format rules + context | | Driver's License | US | Multi-state formats + context | | US Passport | US | Context-required | | Tax ID / EIN | US | Prefix validation + context | | ZIP Code | US | Context-required + validator | | US ITIN | US | Format validation | | IBAN | EU | ISO 7064 mod-97 checksum | | Postal Code | EU | DE/FR/NL patterns | | VAT ID | EU | Country prefix + format | | UK NI Number | UK | Format validation | | UK NHS Number | UK | Modulus-11 checksum | | UK Postcode | UK | Pattern | | UK Passport | UK | Context-required | | UK UTR | UK | Mod-11 checksum | | German Personal ID | DE | Context-required | | German Tax ID | DE | Check digit | | French National ID (NIR) | FR | Check digit | | French SIREN | FR | Luhn checksum | | Spanish DNI | ES | Letter validation | | Spanish NIE | ES | Letter validation | | Spanish NSS | ES | Mod-97 checksum | | Spanish CIF | ES | Custom checksum | | Italian Codice Fiscale | IT | Check digit | | Italian Partita IVA | IT | Luhn-like checksum | | Portuguese NIF | PT | Check digit | | Dutch BSN | NL | Modulus-11 check | | Belgian National Number | BE | Mod-97 checksum | | Belgian Enterprise Number | BE | Mod-97 checksum | | Austrian SVNR | AT | Mod-11 checksum | | Swiss AHV | CH | EAN-13 checksum | | Irish PPS Number | IE | Mod-23 checksum | | Polish PESEL | PL | Check digit | | Polish NIP | PL | Check digit | | Polish REGON | PL | Mod-11 checksum | | Czech Birth Number | CZ | Modulus validation | | Czech ICO (Company ID) | CZ | Mod-11 weighted checksum | | Czech DIC (Tax/VAT ID) | CZ | ICO checksum / mod-11 | | Czech Bank Account | CZ | Mod-11 weighted checksum | | Slovak Birth Number | SK | Modulus validation | | Slovak ICO | SK | Mod-11 weighted checksum | | Slovak DIC | SK | Mod-11 divisibility | | Romanian CNP | RO | Check digit | | Romanian CUI | RO | Mod-11 checksum | | Danish CPR | DK | Date validation | | Danish CVR | DK | Mod-11 checksum | | Swedish Personnummer | SE | Luhn algorithm | | Swedish Organisationsnummer | SE | Luhn algorithm | | Norwegian Birth Number | NO | Check digit | | Norwegian Organisasjonsnummer | NO | Mod-11 checksum | | Finnish HETU | FI | Mod-31 checksum | | Finnish Y-tunnus | FI | Mod-11 checksum | | Hungarian Tax ID | HU | Mod-11 checksum | | Hungarian TAJ | HU | Mod-10 checksum | | Bulgarian EGN | BG | Mod-11 checksum | | Croatian OIB | HR | ISO 7064 MOD 11,2 | | Slovenian EMSO | SI | Mod-11 checksum | | Slovenian Tax Number | SI | Mod-11 checksum | | Lithuanian Personal Code | LT | Dual-pass mod-11 | | Latvian Personal Code | LV | Weighted checksum | | Estonian Personal Code | EE | Dual-pass mod-11 | | Russian INN | RU | Check digit | | Russian SNILS | RU | Check digit | | Canadian SIN | CA | Luhn checksum | | Australian TFN | AU | Mod-11 checksum | | Australian Medicare | AU | Mod-10 checksum | | New Zealand IRD | NZ | Dual-pass mod-11 | | Indian Aadhaar | IN | Verhoeff algorithm | | Indian PAN | IN | Format validation | | Japanese My Number | JP | Mod-11 checksum | | Korean RRN | KR | Weighted checksum | | South African ID | ZA | Luhn checksum | | Turkish Kimlik | TR | Custom dual check | | Israeli ID | IL | Luhn checksum | | Brazilian CPF | BR | Check digit | | Brazilian CNPJ | BR | Check digit | | Argentine CUIT | AR | Mod-11 checksum | | Chilean RUT | CL | Mod-11 with K | | Colombian NIT | CO | Mod-11 prime weights |

Add your API key to unlock names, addresses, organizations, and 60+ additional entity types with NLP-powered detection.