Voice AI platform for businesses

Your phone calls,
answered by AI

AI agents that pick up the phone, have real conversations, and handle everything from bookings to transfers. From $0.08/min.

Get started free Listen to AI demo
$10 free credit·No card required
Real-time
Response
$0.08/min
All inclusive
15+
Languages
99.9%
Uptime SLA
TRUSTED ACROSS INDUSTRIES
Healthcare
Restaurants
Real Estate
Dental Clinics
Hotels
Marketing Agencies
Law Firms
E-commerce
SaaS Companies
Healthcare
Restaurants
Real Estate
Dental Clinics
Hotels
Marketing Agencies
Law Firms
E-commerce
SaaS Companies
HOW IT WORKS
Five steps. Real-time replies.
What happens between the question and the answer.
01
Caller speaks
Voice streams in
02
Transcribed
Voice to text
03
AI thinks
Reads + replies
04
Voice made
Text to speech
05
Caller hears
Natural reply
Real-time
Natural back-and-forth. Faster than a human.
Nixflex real-time
Human ~1.2s
Live demo
Hear the AI speak
One agent. 15 languages. It switches automatically.
CHOOSE A LANGUAGE
Now playing
English · Reception greeting
Supports 15 languages with automatic switching
Real AI voice · Instant playback · No signup required
WHO IT IS FOR
Two ways to go live
Build it yourself, or set it up without writing a line of code.

For developers

Embed voice AI into your own app with one API call. Full control, your stack.

  • REST API, bring your own Twilio
  • 15 languages, automatic switching
  • Webhooks, transfers, custom functions
Read the docs
No code needed

For businesses

Set up your AI receptionist without code. Pick a voice, write what it says, connect a number.

  • Guided setup, no developers
  • Answers 24/7 in any language
  • Far cheaper than the rest
Read the setup guide
FOR DEVELOPERS
One API call.
Your number answers.
Create a voice agent on any phone number. That's it. Everything else is in the docs.
Read the docs
# Create an AI agent
curl -X POST https://api.nixflex.com/v1/agents
-H "Authorization: Bearer YOUR_KEY"
-d '{
"name": "Reception",
"system_prompt": "You are a friendly...",
"voice_id": "Ashley",
"language": "multi"
}'
# Returns agent_id - save it.
# Connect your own Twilio number
curl -X POST https://api.nixflex.com/v1/phone-numbers
-H "Authorization: Bearer YOUR_KEY"
-d '{
"phone_number": "+447446466847",
"twilio_sid": "ACxxxx",
"twilio_token": "xxxx",
"agent_id": "agent_125207e..."
}'
# Your number now answers with AI.
$curl https://api.nixflex.com/v1/calls?limit=1copy
INTEGRATIONS
Every call sends data everywhere
After every call, the full record is sent to your systems — ready to flow anywhere.
Full transcript
Every word, both sides
Recording
MP3 link
AI summary
What was discussed
Sentiment
Happy, neutral, upset
Extracted data
Name, intent, more
FLOWS INTO YOUR TOOLS VIA ZAPIER & MAKE
Zapier
Make
HubSpot
Salesforce
GoHighLevel
Slack
Google Sheets
Airtable
Notion
Connects to your tools via webhooks, Zapier, and Make
No code needed · Data flows after every call
PRICING
Half the price. Everything included.
Others advertise low, then bill you for the LLM, the voice, the telephony, and add-ons. We don’t.
INDUSTRY AVERAGE
~$0.16
per minute, real cost
+ platform fees, add-ons,
up to 5 separate invoices
NIXFLEX
$0.08
per minute, flat · billed per second
Half the price · one bill
Speech recognition
Real-time, 15 languages
AI reasoning
Real-time response
Natural voice
Human-quality speech
Call recording
Stored, plus on your Twilio
Post-call analysis
Summary, sentiment, data
Webhooks
Delivery with auto-retries
Unlimited agents
No per-agent fees
Dashboard + logs
Included
You bring your own Twilio, so phone numbers, carrier minutes, and SMS are billed by Twilio directly at wholesale rates — Nixflex never marks them up.
See full pricing
$10 free credit to start · pay per second · no monthly fee · no setup fee
FAQ
Questions
& answers
What is Nixflex?
+
Nixflex is a developer-first voice AI platform for business phone calls. It combines speech-to-text, a language model, and natural text-to-speech into one real-time engine - so your AI answers, holds a natural conversation, books appointments, transfers to a human, and sends you the full transcript, recording, and data after every call. Bring your own Twilio number, control the AI with a simple prompt, and go live in minutes. Flat $0.08/min with no stacked fees, 15 languages including Arabic.
How does the AI sound so human?
+
We use the latest neural text-to-speech technology with natural voices across 15 languages and accents. The AI responds in real time — faster than most humans — so conversations feel natural and fluid, not robotic.
What languages are supported?
+
We support 15 languages including English (UK, US, Australian), Arabic, French, Spanish, German, Italian, Portuguese, Dutch, Polish, Turkish, Hindi, and many more. Each language has multiple voice options with regional accents.
Can the AI transfer to a human?
+
Yes. The AI supports both warm transfers (AI introduces the caller and provides context before handing over) and cold transfers (instant redirect to the right department). You define the rules for when and how transfers happen.
How long does setup take?
+
Under 5 minutes. Create an account, set up your AI agent with a system prompt, connect your Twilio phone number, and calls are answered immediately. Developers can do it in 5 lines of code.
Can I try it before I pay?
+
Yes. Every new account gets $10 free credit — roughly 125 minutes of calls. No credit card required to sign up. You can test with real calls and only add a payment method when you're ready.
How is Nixflex different from competitors?
+
Four things. Price: at $0.08/min all-inclusive, we are roughly half the real cost of other platforms once their LLM and add-on fees stack up. Speed: real-time responses. Simplicity: you control the AI with a plain prompt - no complex flow-builders - and go live in minutes. And control: bring your own Twilio number (no lock-in), trigger your own APIs live during the call (not just after it), and white-label the whole thing under your own brand. Most platforms only send data after the call ends - Nixflex can act on it mid-conversation.
Can the AI handle accents and background noise?
+
Yes. Our speech recognition engine handles diverse accents and background noise well. It accurately transcribes callers with regional accents, non-native speakers, and people calling from noisy environments.
What's the response latency?
+
Real-time end-to-end — the caller finishes speaking and hears the AI reply right away, faster than average human response time (~1.2s), for a natural back-and-forth.
Can it handle multiple calls at once?
+
Yes. Each account handles 10 concurrent calls by default, and we can raise that up to 50 on request. Inbound calls queue automatically, so callers are never turned away.
Do I need my own Twilio account?
+
Yes — you bring your own Twilio phone number. This means you keep full ownership and control. If you ever leave Nixflex, your number stays with you. Twilio setup takes about 2 minutes.
What data do I get after each call?
+
Full transcript, audio recording with shareable URL, AI-written summary, caller sentiment, extracted data (name, email, intent), and call outcome. All delivered to your webhook automatically.
Can the AI send SMS during a call?
+
Yes. The AI can send SMS during the call (booking confirmations, links) and after the call (summaries, follow-ups). SMS is sent via your own Twilio account — no extra setup needed.
Does the AI handle interruptions?
+
Yes. Barge-in detection stops the AI mid-sentence when the caller starts talking, just like a real human conversation. No talking over each other.
Can I make outbound calls?
+
Yes. Trigger outbound calls via API — the AI calls the number and handles the conversation automatically. Use it for appointment reminders, lead qualification, payment follow-ups, and more.
What if the AI doesn't understand?
+
The AI has fallback responses — it politely asks the caller to repeat or rephrase. If it still can't help, it can transfer to a human, take a message, or offer to call back. You define these rules.
How is billing calculated?
+
Billed per second at $0.08/min. No rounding up — a 45-second call costs $0.06. No monthly fees, no hidden costs, no per-agent charges. Everything included.
Is there a free tier?
+
Every new account gets $10 free credit — roughly 125 minutes. No credit card required. You only add a payment method when your free credit runs out.
How does $0.08/min compare to others?
+
Most platforms advertise a low rate, then add fees for the LLM, voice, and telephony — the real cost averages around $0.16/min. Our $0.08/min is all-inclusive, roughly half the price.
Are there volume discounts?
+
Our price is already flat and simple: $0.08/min for everyone, with no minimums, no tiers, and no negotiation. You pay the same low rate whether you make 10 calls or 10,000.
Are there any hidden fees?
+
No. $0.08/min covers everything. The only separate cost is your Twilio phone number, which you pay directly to Twilio (typically $1-2/month).
Can I cancel anytime?
+
Yes. No contracts. With pay-as-you-go you are only charged for calls already made — stop using it whenever you want, nothing to cancel.
Is my data GDPR compliant?
+
Yes. All data is stored in EU/UK infrastructure (Ireland) and never leaves the EU. Encrypted at rest (AES-256) and in transit (TLS 1.3). Call data auto-deletes after 90 days; you can also delete anything manually.
Where are recordings stored?
+
Recordings are stored by Nixflex, encrypted at rest, and automatically deleted after 90 days. A copy of the original also stays on your own Twilio account, under your own retention — yours to keep or delete.
Who can access my call data?
+
Only you and your authorised team members. All access authenticated with your API key. We never share, sell, or use your call data for training. Your data is yours.
Are calls encrypted?
+
Yes. Audio streams encrypted in transit using WSS and HTTPS. Stored recordings and transcripts encrypted at rest. API calls use TLS. Protected at every stage.
Can I delete my data?
+
Yes. Delete individual calls, recordings, or agents from the API anytime. Call data also auto-deletes 90 days after each call. For full account deletion, email support@nixflex.com and we remove everything within 30 days.

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Real-timeresponses
$0.08/min
15+languages
10-50concurrent
$10 free credit·No card required·Live in 5 minutes
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