--- title: "3 Best Guardrails AI Alternatives in 2026 (Compared)" description: "Looking for a Guardrails AI alternative? Compare the best AI Guardrails & Agent Security alternatives to Guardrails AI by pricing, free tiers, and features — find the right fit for your startup." source: https://appstackbuilder.com/tool-alternatives/guardrails-ai retrieved: 2026-10-17 --- AI Guardrails & Agent Security # The 3 Best Guardrails AI Alternatives in 2026 Looking for an alternative to [Guardrails AI](https://appstackbuilder.com/tools/guardrails-ai)? Below we compare the best ai guardrails & agent security alternatives by pricing, free tiers, and what each is best for — so you can pick the right fit for your budget and stack. Category AI Guardrails & Agent Security Guardrails AI pricing Free tier available Free tier Yes Alternatives 3 compared ## Why look for a Guardrails AI alternative? Guardrails AI is a solid ai guardrails & agent security choice, but it isn't the right fit for everyone. The most common reasons teams evaluate alternatives: * −Owned by Harvey since Sep 2026; roadmap uncertain * −Hosted remote inference ended Aug 2026 * −Mostly checks text in and out, less about tool calls ## Guardrails AI vs Alternatives — Quick Comparison | Tool | Pricing | Free tier | Rating | Best for | | -------------------------------------------------------- | -------------------------- | --------- | ------ | -------------------------------------------------------- | | [Guardrails AI](https://appstackbuilder.com/tools/guardrails-ai)You searched | Free · paid plans by quote | ✓ | 4.4 | AI Guardrails & Agent Security — guardrails, validation | | 1.[Lakera Guard](https://appstackbuilder.com/tools/lakera-guard) | Free · paid plans by quote | ✓ | 4.5 | AI Guardrails & Agent Security — guardrails, ai-security | | 2.[NVIDIA NeMo Guardrails](https://appstackbuilder.com/tools/nemo-guardrails) | Free | ✓ | 4.5 | AI Guardrails & Agent Security — guardrails, ai-security | | 3.[Amazon Bedrock Guardrails](https://appstackbuilder.com/tools/bedrock-guardrails) | From $0.15/mo | — | 4.4 | AI Guardrails & Agent Security — guardrails, ai-security | ## Top Guardrails AI Alternatives, Explained ![Lakera Guard](https://www.google.com/s2/favicons?domain=lakera.ai&sz=128) ### 1. Lakera Guard Free tier4.5· Free · paid plans by quote Lakera Guard is a security API you call before and after the model. It detects prompt injection, jailbreaks and adversarial instructions, sensitive-data exposure, harmful output and, for agents, unsafe tool use, including indirect injection that arrives through MCP-connected tools. Lakera claims sub-50 ms latency and coverage of 100+ languages, and its detectors are informed by Gandalf, its public prompt-injection game. Check Point announced its acquisition of Lakera in September 2025, and Lakera now sits inside Check Point's AI security portfolio. You can start free on the Community plan; production volumes, self-hosting and SLAs are quoted by sales. * ✓Purpose-built prompt-injection detection * ✓Sub-50 ms claimed latency * ✓Covers agent tool use and MCP injection [Lakera Guard pricing & review ](https://appstackbuilder.com/tools/lakera-guard)[Guardrails AI vs Lakera Guard ](https://appstackbuilder.com/compare/guardrails-ai-vs-lakera-guard) ![NVIDIA NeMo Guardrails](https://www.google.com/s2/favicons?domain=nvidia.com&sz=128) ### 2. NVIDIA NeMo Guardrails Free tier4.5· Free NeMo Guardrails sits between your app and the model and enforces rules you define: input rails screen or rewrite user messages, dialog rails keep the conversation on approved paths, retrieval rails filter RAG chunks, execution rails check the inputs and outputs of tools the model calls, and output rails block or fix responses. Rules are written in Colang, a Python-like modeling language. It ships jailbreak and injection detection, self-check moderation and hallucination rails, NVIDIA safety models, and integrations with services such as ActiveFence. It runs as a Python library or a server, works with LangChain, and is free under Apache-2.0 (latest release 0.24.1, September 2026). Usage telemetry is on by default and can be turned off. * ✓Backed by NVIDIA, Apache-2.0 * ✓Rails for tool calls as well as chat * ✓Dialog control no classifier API offers [NVIDIA NeMo Guardrails pricing & review ](https://appstackbuilder.com/tools/nemo-guardrails)[Guardrails AI vs NVIDIA NeMo Guardrails ](https://appstackbuilder.com/compare/guardrails-ai-vs-nemo-guardrails) ![Amazon Bedrock Guardrails](https://www.google.com/s2/favicons?domain=aws.amazon.com&sz=128) ### 3. Amazon Bedrock Guardrails 4.4· From $0.15/mo Bedrock Guardrails applies configurable safeguards to model inputs and outputs: content filters for hate, violence, sexual content and prompt attacks (text and images), denied topics you describe in plain language, word filters, PII and regex masking, contextual grounding checks for hallucination against a source, and Automated Reasoning checks against logical rules. Through the ApplyGuardrail API it works with any model, including OpenAI, Gemini and self-hosted models, not only those on Bedrock, and security teams can enforce one guardrail across an AWS organization. Pricing is per 1,000 text units (up to 1,000 characters each): content filters and denied topics $0.15, sensitive-information filters and contextual grounding $0.10, word filters and regex free, Automated Reasoning $0.17 per policy. Input and output are each charged. * ✓Published per-unit pricing * ✓Works with any model via ApplyGuardrail * ✓Org-wide enforcement across AWS accounts [Amazon Bedrock Guardrails pricing & review ](https://appstackbuilder.com/tools/bedrock-guardrails)[Guardrails AI vs Amazon Bedrock Guardrails ](https://appstackbuilder.com/compare/bedrock-guardrails-vs-guardrails-ai) [In-depth guideBest AI Guardrails 2026: NeMo Guardrails vs Guardrails AI vs Lakera Guard vs Bedrock GuardrailsPrompt injection, jailbreaks, leaked personal data and agents calling tools they should not. Two open-source guardrail frameworks and two hosted services compared on what they catch, where they sit, and what a million messages costs.](https://appstackbuilder.com/blog/best-ai-guardrails-tools-2026) ## Frequently Asked Questions What are the best alternatives to Guardrails AI in 2026?⌄ The best Guardrails AI alternatives in 2026 are Lakera Guard, NVIDIA NeMo Guardrails, Amazon Bedrock Guardrails. Each is a ai guardrails & agent security option you can compare on pricing, free tiers, and features in the table above. Is there a free alternative to Guardrails AI?⌄ Yes — Lakera Guard, NVIDIA NeMo Guardrails offer free tiers, making them strong free Guardrails AI alternatives for bootstrapped startups. Why look for a Guardrails AI alternative?⌄ A common reason teams switch is owned by harvey since sep 2026; roadmap uncertain. Beyond that, people compare ai guardrails & agent security tools on pricing, specific feature gaps, ease of use, and whether an open-source or free-tier option exists — so they can pick the best fit for their stack and budget. What is the cheapest Guardrails AI alternative?⌄ Lakera Guard is among the most affordable Guardrails AI alternatives — free · paid plans by quote. Check the comparison table above for the full pricing breakdown. Which Guardrails AI alternative is rated highest?⌄ Lakera Guard is the highest-rated Guardrails AI alternative in our catalog at 4.5 out of 5, making it a strong pick if you want a well-reviewed option. ## Find your perfect ai guardrails & agent security tool Skip the research. Get a free AI-powered tech stack matched to your budget, app type, and team size in seconds. [Build my stack free ](https://appstackbuilder.com/)