The AI privacy tool landscape has exploded. Open-source projects, commercial SaaS platforms, and browser extensions all promise to keep your data safe from AI models. Here’s how they actually compare.
The Contenders
Open-Source Proxy Solutions
AI Privacy Gateway (MIT License)
- Type: Local proxy server
- Deployment: Docker, 30-second setup
- PII Detection: 14+ entity types (regex-based, < 1ms latency)
- Supports: All OpenAI-compatible APIs
- Key advantage: Zero external dependencies, fully local
- Stars: Growing
LLM Guard (MIT License)
- Type: Python SDK + optional proxy
- Deployment: pip install
- PII Detection: Regex + transformers (slower but more accurate)
- Supports: Multiple providers
- Key advantage: Python ecosystem integration
- Stars: 500+
PasteGuard (MIT License)
- Type: Browser extension (WASM-based)
- Deployment: Chrome Web Store
- PII Detection: Client-side regex
- Supports: Web-based AI chat interfaces
- Key advantage: No infrastructure, browser-native
- Stars: 654
Commercial Solutions
Nightfall AI
- Type: Cloud DLP platform
- Deployment: API integration
- PII Detection: ML-based (highest accuracy)
- Key advantage: Enterprise DLP integration, compliance reporting
- Pricing: Per-seat licensing
Private AI
- Type: SDK + cloud
- Deployment: On-premise or cloud
- PII Detection: NER-based (trained on PII datasets)
- Key advantage: High accuracy for unstructured text
- Pricing: Enterprise licensing
Comparison Table
| Feature | AI Privacy Gateway | LLM Guard | PasteGuard | Nightfall | Private AI |
|---|---|---|---|---|---|
| License | MIT | MIT | MIT | Commercial | Commercial |
| Deployment | Docker | pip | Extension | API | SDK/Cloud |
| Setup time | 30s | 5 min | 1 min | 1 hour | 1 hour |
| PII types | 14+ | 10+ | 8+ | 30+ | 50+ |
| Latency | < 1ms | ~5ms | < 0.5ms | ~50ms | ~100ms |
| HTTPS support | Yes (MITM) | Yes (proxy) | Browser-only | API-based | API-based |
| Audit logging | Yes | Limited | No | Yes | Yes |
| Offline operation | Yes | Yes | Yes | No | Partial |
| Cost | Free | Free | Free | $$$$ | $$$ |
Choosing the Right Tool
Individual Developer: PasteGuard or AI Privacy Gateway
If you only use web-based AI tools, a browser extension like PasteGuard is the simplest option. If you use API-based tools (Claude Code, Cursor API mode, custom scripts), you need a proxy like AI Privacy Gateway.
Small Team: AI Privacy Gateway
Deploy a shared proxy instance in 30 seconds. Everyone on the team points their AI tools to it. Centralized management, zero per-seat cost.
Enterprise: AI Privacy Gateway + Commercial DLP
Layer a privacy proxy for real-time PII masking with a commercial DLP platform for compliance reporting and policy management.
The Bottom Line
Open-source AI privacy tools are mature enough for production use in 2026. The key question isn’t “which tool is best?” — it’s “are you using any tool at all?” The biggest risk is unprotected AI usage.