---
title: "Locke vs Prompt Security"
description: "Prompt Security is a broad GenAI security platform inspecting prompts and responses. Locke is a local-first, zero-knowledge control for sensitive data in prompts. How they compare — verify specifics with the vendor."
url: "https://sonomos.ai/compare/sonomos-vs-prompt-security/"
source: "https://sonomos.ai/compare/sonomos-vs-prompt-security/"
---

# Locke vs Prompt Security

Prompt Security is a GenAI security platform covering the full range of LLM risks. It prevents sensitive-data leakage to AI tools, defends homegrown LLM apps against prompt injection and jailbreaks, and surfaces shadow AI. It inspects prompts and model responses across many models, as SaaS or on-premise, with a browser extension for employees and an API for in-house apps. (Prompt Security was reported to be acquired by SentinelOne; ownership and packaging may continue to evolve, so confirm current details with the vendor.) Prompt Security is a broad suite that inspects content through its platform. Locke is a focused, local-first, zero-knowledge control for sensitive data in prompts. (Category-level as of 2026; verify specifics with the vendor.)

## When Prompt Security fits

- You need broad GenAI security: prompt-injection and jailbreak defence for homegrown LLM apps, plus employee-facing controls.
- You want one platform covering shadow-AI discovery, response inspection, and policy across many models.
- Your security team prefers a managed platform (SaaS or on-premise) with centralised GenAI policy enforcement.

## When Locke fits

- Your priority is sensitive data in prompts, detected and masked on the device before anything is sent.
- Zero-knowledge is a hard requirement: no platform should inspect the content you are protecting.
- You want a per-user Early Access desktop app (Locke), free for one person, rather than a full GenAI-security suite.

## Side-by-side

| Dimension | Locke | Prompt Security |
| --- | --- | --- |
| Scope | Sensitive data in AI prompts, masked on the device. | Broad GenAI security: leakage, injection, jailbreaks, shadow AI. |
| Where inspection runs | On the device, before any network call. | Through the platform (SaaS or on-premise), inspecting content. |
| Trust model | Zero-knowledge: the vendor never sees prompt content. | Content is inspected by the platform to enforce policy. |
| Entry point | Locke Free costs nothing (Early Access); Teams starts at $14.99 per seat a month. | Commercial platform. Contact vendor for current pricing. |
| Best for | Local-first, zero-knowledge control of AI prompts. | End-to-end GenAI security across apps and employee use. |

## Bottom line

Prompt Security is a broad GenAI-security platform, useful if you also need injection defence for your own LLM apps and centralised policy across employee AI use. Locke is narrower and local by design: it keeps sensitive prompt data on the device, with nothing for a vendor to inspect. For full GenAI-security coverage, look at Prompt Security. If local-first and zero-knowledge come first, choose Locke. Confirm current capabilities and ownership with the vendor.

[Download Locke](https://sonomos.ai/downloads/)[See the Locke demo](https://sonomos.ai/locke/#demo)[See pricing](https://sonomos.ai/pricing/)[Talk to the team](https://sonomos.ai/contact/)

## Related comparisons

- [Locke vs Nightfall AI](https://sonomos.ai/compare/sonomos-vs-nightfall-ai/)
- [Locke vs Private AI](https://sonomos.ai/compare/sonomos-vs-private-ai/)
- [Locke vs Strac](https://sonomos.ai/compare/sonomos-vs-strac/)

[View all comparisons](https://sonomos.ai/compare/)

## Further reading

- [The Best AI Privacy Tools for ChatGPT, Claude, and Gemini (2026)](https://sonomos.ai/blog/best-ai-privacy-tools-chatgpt-claude-gemini-2026/)
- [AI Data Leakage: 7 Ways Sensitive Information Escapes to LLMs (and How to Stop It)](https://sonomos.ai/blog/ai-data-leakage-7-ways-sensitive-info-escapes-to-llms/)
- [What Is PII Redaction? A Plain-English Guide for AI Users](https://sonomos.ai/blog/what-is-pii-redaction-ai/)