Moderation and safety

Prompt Guard

Tiny classifiers that catch attempts to hack a bot: prompt injections and rule bypassing. The 86M version is multilingual, 22M is English only.

Developer
Meta, USA
First release
Jul 2024
Latest release
Apr 2025
Sizes
22M – 86M
License
Commercial use with conditionsLlama 3.1 and 4 licenses: commercial use allowed with restrictions
Russian
Not supported
Running
On your own serverAlso runs without a GPU
Industries
Security, Software development
Deploy on your server Hugging Face GitHub

What it does

  • Protecting a bot from prompt injections
  • Checking emails and documents that reach an AI agent
  • Fast filter in front of a large model

Where it is used

Chatbots and AI agentsInformation security

Hardware requirements

LaptopLaptop or regular PC, up to 8 GB of VRAM — smaller versions
fits
1 GPUOne GPU with 16–80 GB — mid-size versions
no versions
ClusterServer with several GPUs — flagship versions
no versions

Versions

  1. Llama Prompt Guard 2 22M и 86M
  2. Prompt Guard 86M

How to run it

On your own serverWeights are downloaded from Hugging Face and served with vLLM (load and API) or llama.cpp (modest hardware). The model then runs in a closed network with no per-request fees.Hugging Face
How much hardware you needCalculate the VRAM for the model size, context length and number of concurrent requests.Open the hardware calculator

I can set this up end to end: pick the model size, deploy it on your server and connect it to your systems.

Frequently asked questions

Can Prompt Guard be used in a commercial project?

With conditions. License: Llama 3.1 and 4 licenses: commercial use allowed with restrictions. Restrictions vary — region, company revenue, attribution requirements. Have a lawyer check the terms before a commercial launch.

What hardware does Prompt Guard need?

At minimum: Laptop or regular PC, up to 8 GB of VRAM — smaller versions. Some versions also run on an ordinary CPU, without a GPU. You can calculate the exact VRAM for your model size and context in the hardware calculator.

Does Prompt Guard support Russian?

No. The model card lists its languages and Russian is not among them.

Where can I download Prompt Guard and what does it cost?

The Prompt Guard weights are open and free to download. You only pay for the hardware it runs on and for the setup. Source links are at the bottom of this page.

How I deploy it for clients

  1. SelectionI pick the model size for your task and hardware and test it on your examples.
  2. DeploymentI deploy it on your server or in a closed network and provide an API.
  3. Fine-tuningI fine-tune it on your data (LoRA) or connect a knowledge base — whichever is cheaper for the task.
  4. IntegrationI connect it to your CRM, ERP, bot, website or team chat and set up monitoring.

Similar models

Moderation and safetyLlama GuardMeta · USACommercial use with conditions

Filter models that check chatbot requests and replies for dangerous topics against a list of categories. Version 4 also checks images. Russian is not officially supported.

DetailsModeration and safetyGranite GuardianIBM · USACommercial use allowed

IBM judge models: they catch harm, profanity and jailbreak attempts, and in RAG and agents check whether an answer is grounded in the documents. You can state your own rule in words.

DetailsModeration and safetyQwen3GuardAlibaba (Qwen) · ChinaCommercial use allowed

Safety filters for 119 languages, Russian among them. The Stream version checks a bot's reply while it is being generated and can cut it off on the fly.

Details

Source: huggingface.co/meta-llama/Llama-Prompt-Guard-2-22M. Data checked against the model card on 22 Sep 2026. Have a lawyer review the license before commercial launch.