Tone

Free plan APISelf-hostedWeb

What Tone is

Tone is an open-source voice AI platform for building, deploying, and self-hosting voice agents. Agents can handle inbound and outbound calls, web widgets, or chat, combining prompts, tools, workflows, configurable models, voices, and speech-to-text providers. Its knowledge base can ingest PDFs, scraped documents, Notion, and Confluence content, with retrieval, re-ranking, citations, and custom vocabulary. A visual workflow builder supports branching, loops, human handoff, TypeScript hooks, and triggers from Zapier, REST API, or HighLevel. The test center runs simulated calls with different personas, accents, and edge cases, supports parallel regression runs, and replays production calls. Observability covers measures and signals such as latency, interruptions, sentiment, and real-time alerts. Developers can use a TypeScript-first SDK, CLI, hosted API, or self-host with Docker Compose and a Kubernetes Helm chart. Tone is MIT licensed and lists 29 supported languages. The Self-host plan is free; Cloud costs $0.09 per minute and includes $10 free credit with no card required.

Who it suits

Tone suits developers building voice agents for calls, web widgets, or chat, especially those needing workflow controls, testing, and call observability. It also serves teams that want self-hosting or a hosted API.

What it does well

Free MIT-licensed self-host plan.
Supports inbound and outbound calls.
Includes human handoff in workflows.
Supports 29 languages.
Offers Docker Compose and Helm deployment.

What to know first

Cloud is billed at $0.09 per minute.
Enterprise pricing is custom and not listed.
Self-host customers receive community Discord support.

Limits

The Self-host plan is free and lists unlimited agents, calls, and workflows, but requires bringing your own LLM, voice, and telephony. Cloud is billed at $0.09 per minute and includes $10 in free credit.

Plans

Plan	Billed and limits	Price
Self-host	$0 · Unlimited agents, calls, workflows · Bring your own LLM, voice, telephony · Docker Compose & Helm chart · Community Discord support · All integrations included	Free
Cloud	$0.09 per minute · $10 free credit, no card required · Auto-scaling worker fleet · 99.99% uptime SLA · SOC 2 Type II · HIPAA-ready · Email & chat support · Pay-as-you-go, cancel anytime	$0.09 a month
Enterprise	Custom · Single-tenant or on-prem · BAA, DPA, custom contracts · Dedicated support and Slack channel · Custom integrations and roadmap · Audit logs, SSO/SAML, RBAC	On request

As trytone.ai lists them, read 30 Sept 2026. The maker's own page has the final word.

Getting started

Open the Tone website.
Choose the free Self-host plan or Cloud plan.
For self-hosting, start with Docker Compose or use the Kubernetes Helm chart.
For Cloud, use the hosted API; the plan includes $10 in free credit and requires no card.
Build an agent from prompts, tools, workflows, models, voices, and speech-to-text providers.

Verdict

Tone combines agent building, deployment, testing, and monitoring in one voice AI platform. Choose between free self-hosting, usage-priced Cloud, or custom Enterprise terms.

Questions

Is Tone free?

Yes. Its Self-host plan costs nothing and includes unlimited agents, calls, and workflows. Cloud includes $10 in free credit and is billed at $0.09 per minute.

Can I self-host Tone?

Yes. Self-hosting is available through Docker Compose, and Tone includes a Kubernetes Helm chart.

What platforms does Tone support?

Tone is available through the web, API, and self-hosted deployment.

Is Tone open source?

Yes. Tone is MIT licensed, and its agent runtime, call routing, and evaluation harness are published on GitHub.

What integrations are available?

Listed integrations include OpenAI, Anthropic, Google Gemini, Mistral, Llama, ElevenLabs, Deepgram, Twilio, HubSpot, Salesforce, Zapier, Slack, Notion, and Confluence, among others.

Who makes Tone, and where is it based?

Tone lists headquarters in Bengaluru and San Francisco.

Facts from Tone's own pages

Agent channels: Agents can run inbound, outbound, web-widget, or chat experiences. · trytone.ai, 30 Sept 2026
Agent composition: Agents combine prompts, tools, workflows, configurable models, voices, and speech-to-text providers. · trytone.ai, 30 Sept 2026
Developer access: Tone provides a TypeScript-first SDK, CLI, local Docker development loop, composable runtime, and hosted API access. · trytone.ai, 30 Sept 2026
Headquarters: Bengaluru and San Francisco · trytone.ai, 23 Sept 2026
Integrations: Listed integrations include OpenAI, Anthropic, Google Gemini, Mistral, Llama, ElevenLabs, Cartesia, PlayHT, Deepgram, Whisper, AssemblyAI, Twilio, Telnyx, Plivo, LiveKit, HubSpot, Salesforce, Zapier, n8n, Slack, Notion, Confluence, and GoHighLevel. · trytone.ai, 30 Sept 2026
Knowledge base: Tone ingests PDFs, scraped documents, Notion, and Confluence content and provides chunking, embeddings, retrieval, re-ranking, citations, and custom vocabulary. · trytone.ai, 30 Sept 2026
Observability: Observability includes interruption rate, latency, sentiment, gibberish detection, stereo recordings, waveform inspection, custom dashboards, and real-time alerts. · trytone.ai, 30 Sept 2026
Open-source license: Tone is MIT licensed and its agent runtime, call routing, and evaluation harness are published on GitHub. · trytone.ai, 30 Sept 2026
Performance: The product page states a 218 ms voice-loop p50, 120 ms time-to-first-byte, 10k+ concurrent calls per region, 29 supported languages, and a 99.99% Cloud uptime SLA. · trytone.ai, 30 Sept 2026
Security posture: The site states SOC 2 Type II, HIPAA-ready, and GDPR compliance, and the changelog says edge PII redaction and HMAC-SHA256 webhook signing were added. · trytone.ai, 30 Sept 2026
Self-hosting: Tone can be started with Docker Compose and includes a Kubernetes Helm chart, with Postgres, Redis, and ClickHouse in the example stack. · trytone.ai, 30 Sept 2026
Support: Self-host customers receive community Discord support, Cloud customers receive email and chat support, and Enterprise customers receive dedicated support with a Slack channel. · trytone.ai, 30 Sept 2026
Testing: The test center runs simulated calls with personas, accents, and edge cases, supports parallel regression runs, and replays production calls. · trytone.ai, 30 Sept 2026
What it does: Tone is an open-source voice AI platform for building, deploying, and self-hosting voice agents. · trytone.ai, 30 Sept 2026
Workflow builder: The visual workflow builder supports branching, loops, human handoff, TypeScript hooks, and triggers from Zapier, REST API, or HighLevel. · trytone.ai, 30 Sept 2026

Where Tone stands on Freedom251

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