SafePrompt · Prompt injection detection API
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SafePrompt
Prompt injection detection API by Reboot Inc.
Built against OWASP LLM01Benchmark suite v2.0 · 150 promptsOpen-source SDK · MIT

Simple, Transparent Pricing

Every plan runs the same detection engine, so accuracy does not depend on what you pay. Paid plans add higher rate limits, IP threat intelligence, and the option to stop contributing attack data.

Cancel anytime
No setup fees
No per-request fees

Free

$0/month

For side projects and evaluation

Free • 100,000 requests/month

100,000 validations/month
10 requests/second
Instant self-serve signup
Full AI protection (same engine)
Pattern + AI validation
Multi-turn attack detection
Contributes attack data to network defense (no opt-out on free)
GDPR export/delete
Basic usage dashboard (top-3 attacks)
RECOMMENDED

Starter

$29/month

For a live app with real users

Instant access • Cancel anytime

500,000 validations/month
50 requests/second

Everything in Free, plus:

IP-based threat intelligence
Intelligence opt-out option
Advanced threat detection
Usage analytics dashboard (24h / 7d / 30d timeline)
Detection-method breakdown
Top-10 attack categories
SCALE

Business

$99/month

For teams running at volume

Scale with confidence

1,000,000 validations/month

Everything in Starter, plus:

Priority email support
100 custom whitelist phrases
100 custom blacklist phrases
Dedicated support channel
100 requests/second
Fully managed infrastructure
Network-wide attack campaign feed
Auto-discovered pattern proposals
Full attack taxonomy (14 categories)

What happens if you hit your monthly limit

Requests past your plan's monthly limit are rejected with an HTTP 429 response that includes the date your quota resets. Nothing is charged automatically and there is no overage billing, so you cannot get a surprise invoice. Your traffic keeps flowing again at the reset date, or immediately if you upgrade. Decide in advance how your app should behave if validation is unavailable, and see the fail-open and fail-closed guidance in the docs.

Frequently Asked Questions

How much does prompt injection detection cost?

SafePrompt prompt injection detection starts at $0/month with a free tier (100,000 validations/month). The Starter plan is $29/month for 500,000 validations. The Business plan is $99/month for 1,000,000 validations. Every plan runs the same detection engine. No per-request fees, no hidden costs, no credit card required for the free tier.

Is there a free prompt injection API?

Yes. SafePrompt offers a free tier with 100,000 API validations per month at no cost. The free tier uses the same detection engine as paid plans — pattern detection, external reference detection, and AI validation. No credit card is required. Sign up with your email and get instant access. One difference to know before you choose it: free-tier validations contribute anonymised attack patterns to the shared network defence and cannot opt out. Paid plans can turn that off in Privacy Settings.

What's included in SafePrompt's free tier?

SafePrompt's free tier includes 100,000 validations per month, full AI protection (same engine as paid plans), pattern and AI validation, multi-turn attack detection, and network defense contribution. You get GDPR-compliant data export and deletion. The main limitations vs paid plans are no priority support and no intelligence opt-out.

Is the free plan really free?

Yes! Sign up and confirm your email for instant access: 100,000 requests/month, no credit card required and no time limits.

Can I change plans later?

Yes! Upgrade anytime, downgrade at the end of any billing cycle. No contracts or penalties.

Can I cancel anytime?

Yes. Cancel anytime from your dashboard. No cancellation fees, no questions asked.

Do I need a credit card for free?

No credit card needed. Sign up with just your email and start protecting your AI apps immediately.

What's included in all plans?

Every plan uses our full AI validation engine with pattern detection, multi-turn attack protection, and network defense.

Can I upgrade from Free to Starter?

Yes! You can upgrade from your dashboard settings anytime. Instant access as soon as payment is confirmed.

Do I get locked into a specific LLM provider?

No. SafePrompt validates input before it reaches your model, so it works with OpenAI, Anthropic, Google, Mistral, and any other LLM. Switch providers anytime, with no vendor lock-in, and export or delete your data on any plan.

Why pay when open-source tools like LLM Guard are free?

Open-source filters are free to license but you self-host, maintain, and scale them yourself. SafePrompt is fully managed and always-on: one API call, no infrastructure to run, and a free tier so you can start without a credit card.