Voice AI Guardrails

Comprehensive protection at every stage of your Voice AI pipeline. From validating inputs to filtering outputs, ensure only high-quality, safe, and compliant content flows through your applications.

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Operational Guardrails

Quality control

Speech Threshold

Transcribe only files with a minimum percentage of spoken audio.

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Set the Start and End of the Transcript

Limit transcription to sections containing speech.

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Safety Guardrails

Production-ready safety

Content Moderation

Detect sensitive content in your audio and video files - such as hate speech, violence, sensitive social issues, alcohol, drugs, and more.

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PII Redaction

Identify and remove Personally Identifiable Information, such as phone numbers and social security numbers, from the transcription text before it is returned to you.

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PII Audio Redaction

Replace Personally Identifiable Information, such as phone numbers and social security numbers in your audio files with a "beep" for compliance.

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Profanity Filtering

Identify and redact profane or sensitive terms, keeping your speech-to-text output clean and compliant across any application.

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AssemblyAI’s built-in PII redaction and PCI compliance features were crucial as European GDPR enforcement tightened. Our customers explicitly require these capabilities, and they directly support our compliance strategy.”
— Raj Shankar, Calabrio

Continuously 
up-to-date 
and secure

Regular enhancements

Explore our changelog for detailed updates on the most recent product enhancements and improvements.

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Enterprise-grade security

AssemblyAI is committed to the highest standards of security practices to keep your data and your customers' data safe.

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Pre-recorded Speech-to-Text

Build on top of the most accurate Speech-to-Text model on the market with >93.3% accuracy.

Streaming Speech-to-Text

Transcribe audio streams synchronously with high accuracy and low latency.

Frequently Asked Questions

What are AssemblyAI's Voice AI Guardrails?

Voice AI Guardrails are AssemblyAI’s built-in safety features that keep voice pipelines safe and compliant. They ensure only high‑quality content flows through your app by providing: Profanity Filtering, Content Moderation, and PII Redaction in both text and audio (PII Audio Redaction).

What is Content Moderation for Voice AI?

Content Moderation for voice AI is AssemblyAI’s model that detects sensitive or inappropriate topics in audio/video (e.g., hate speech, violence, drugs). It flags segments with labels, confidence, timestamps, and context-aware severity (low/medium/high), enabling you to filter, review, or route content based on policy.

Does AssemblyAI provide GDPR and PCI compliance features?

Yes. AssemblyAI supports GDPR and PCI. It states GDPR compliance and includes a DPA. Its Security & Privacy program lists PCI DSS. Guardrails like PII redaction further support regulated use cases.

 How do I implement Voice AI Guardrails?

 Enable Guardrails features in your STT pipeline via API options: turn on Profanity Filtering, Content Moderation, and PII Redaction (text or audio), and configure operational controls like Speech Threshold and transcript start/end. These validate inputs and filter outputs to keep content safe and compliant.

Can I use Guardrails with Streaming Speech-to-Text?

Yes. Guardrails can be used with Streaming Speech-to-Text. Operational controls like Speech Threshold are supported across all models, and safety Guardrails—PII Redaction, PII Audio Redaction, Content Moderation, and Profanity Filtering—provide pipeline-wide protection to validate inputs and filter outputs alongside your streaming transcripts.

What is the pricing for Voice AI Guardrails?

Voice AI Guardrails are billed pay‑as‑you‑go by audio duration (pro‑rated per second). Current rates: Profanity Filtering $0.01/hr; PII Audio Redaction $0.05/hr; PII Redaction $0.08/hr; Content Moderation $0.15/hr. See the Pricing page for details.

Which Guardrails work with Pre-recorded Speech-to-Text?

Pre-recorded Speech-to-Text supports these Guardrails: Speech Threshold; Set Start and End of Transcript; PII Redaction (text); Profanity Filtering; and Content Moderation. These controls limit transcription to speech-only segments, remove PII, and filter unsafe or profane content in batch transcription workflows.

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