Staxly

ElevenLabs vs Knock

Best-in-class AI text-to-speech + voice cloning + Conversational AI
vs. Notifications-as-a-service: in-app feeds, email, push, SMS, chat via one API

ElevenLabs websiteKnock website

Pricing tiers

ElevenLabs

Free
10k credits/month. No voice cloning. Limited API.
Free
Starter
$6/mo. 30k credits. Instant voice cloning. Limited API.
$6/mo
Creator
$11/mo (first month 50% off). 121k credits. Professional cloning. Full API.
$11/mo
Pro
$99/mo. 600k credits. 44.1 kHz PCM API. Professional cloning.
$99/mo
Scale
$299/mo. 1.8M credits. 3 professional voice clones.
$299/mo
Business
$990/mo. 6M credits. 10 pro clones. Low-latency TTS API.
$990/mo
Enterprise
Custom. Unlimited pro clones + full access.
Custom
ElevenLabs website

Knock

Developer
Free forever. 10K messages, 500 guide users, 500 AI credits/month.
$0 base (usage-based)
Starter
$250/mo. 50K messages, 2.5K guide users, 2K AI credits. Remove branding.
$250/mo
Enterprise
Custom pricing. White-label, i18n, data warehouse, Datadog, SCIM, SAML, HIPAA/BAA.
Custom
Knock website

Free-tier quotas head-to-head

Comparing free on ElevenLabs vs starter on Knock.

MetricElevenLabsKnock
guide users2500 users
guide users overage$0.05/user USD/user
messages monthly50000 messages/mo
messages overage$0.005/message USD/message

Features

ElevenLabs · 13 features

  • Conversational AIVoice agents with LLM orchestration + tools.
  • Dubbing StudioAuto-dub video to target languages with lip-sync.
  • ProjectsLong-form narration workflow — books, podcasts.
  • Realtime StreamingLow-latency TTS streaming via WebSocket.
  • Scribe (STT)High-accuracy speech-to-text with speaker diarization.
  • Sound EffectsAI-generated SFX from text prompts.
  • Text to SoundGenerate music + sound from text.
  • Text-to-SpeechStudio-quality TTS across 29 languages with emotion control.
  • Voice ChangerTransform one voice into another preserving delivery.
  • Voice CloningInstant (short sample) + Professional (30 min +) voice cloning.
  • Voice DesignDesign voices from text descriptions.
  • Voice Library3,000+ community voices. License per-voice.
  • Voiceover StudioMulti-character voiceover timeline.

Knock · 13 features

  • AI AgentsAutonomous notification drafting & workflow generation.
  • Batch + DigestGroup notifications into digests on schedule or window.
  • ChatSlack, Microsoft Teams, Discord.
  • EmailSend via SendGrid/Postmark/Resend/Mailgun/AWS SES as relays.
  • GuidesIn-product messaging, announcements, modals, banners.
  • i18n / LocalizationTranslate templates by user locale.
  • In-App FeedNotification inbox with React/Vue/iOS/Android drop-in components.
  • Multi-tenancyPer-tenant branding, preferences, quiet hours.
  • Outbound WebhooksSubscribe to delivery events.
  • PreferencesUser + tenant preference center with granular controls.
  • PushiOS (APNs), Android (FCM), Expo, Web Push.
  • SMSTwilio, MessageBird, Telnyx, Vonage as providers.
  • WorkflowsVisual notification orchestration (branch, batch, delay, throttle).

Developer interfaces

KindElevenLabsKnock
CLIKnock CLI
SDKelevenlabs (Node), elevenlabs (Python)knockapi (Python), knockapi (Ruby), knock-elixir, knock-go, knock-java, @knocklabs/node, @knocklabs/react
RESTElevenLabs REST APIKnock REST API
MCPElevenLabs MCPKnock MCP Server
OTHERWebhooks, WebSocket StreamingOutbound Webhooks
Staxly is an independent catalog of developer platforms. Some links to ElevenLabs and Knock may be affiliate links — Staxly may earn a commission if you sign up through them, at no extra cost to you. Pricing is verified against vendor pages at publication time — reconfirm before buying.

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