Voice AI Running Costs Calculator
Voice AI combines several technologies working together—AI processing, voice infrastructure, telephony, and messaging—each with its own pricing structure. Understanding what this will actually cost your business shouldn't require a degree in mathematics.
Whether you're exploring automation for customer service, appointment booking, or outbound campaigns, this calculator gives you realistic monthly estimates based on current UK market rates. Simply enter your anticipated call volume and average conversation length. Our tool factors in all the essential components: AI processing (OpenAI), telephony costs (Twilio), voice infrastructure (Retell AI), and SMS confirmations where applicable.
Important Notice: This calculator provides indicative estimates only, based on third-party provider pricing (OpenAI, Twilio, Retell AI) that we update regularly but which may change without notice. It does not constitute financial advice or a binding quotation. Actual costs will vary depending on your usage patterns, provider agreements, currency rates, and specific requirements. This tool is provided "as is" without warranties, and we accept no liability for decisions made based on these estimates.
Understanding Voice AI Costs
Voice AI isn't a single service—it's an orchestra of technologies working in harmony. Understanding the components helps you make informed decisions and optimize your investment.
The Four Cost Components: Your voice AI conversation relies on four distinct layers, each contributing to the total cost. The orchestration layer manages conversation flow, detecting when callers finish speaking and handling interruptions smoothly. The intelligence layer powers understanding and responses through language models—think of this as your agent's brain. The voice layer converts speech to text and text back to natural-sounding speech. Finally, the telephony layer connects calls through the phone network.
What Drives Your Costs: Call duration matters most—longer conversations consume more resources across all layers. The sophistication of your AI model affects intelligence costs: basic scripted responses cost less than complex reasoning. Voice quality impacts synthesis expenses: standard voices are economical, whilst premium neural voices sound remarkably human but cost more. For UK businesses, whether you're calling mobiles or landlines significantly affects telephony charges, with mobile termination rates running 50-80% higher.
Hidden Variables to Consider: Not all calls connect. Outbound campaigns typically reach 20-40% of attempts, and some providers charge for failed connection attempts. Billing increments matter too—providers round call duration differently, from per-second precision to 60-second blocks. Peak concurrency affects costs if you need multiple simultaneous lines during busy periods. UK-specific factors include VAT treatment and currency fluctuation between USD-denominated services and your GBP budget.
Where You Can Optimize: Choose AI models appropriate to your use case—appointment confirmations don't need the same sophistication as complex negotiations. Optimize conversation design to achieve objectives efficiently without unnecessary dialogue. Consider your number mix carefully; routing more calls to landlines where possible reduces costs. For high volumes, providers offer preferential rates that can substantially reduce your per-minute costs.
This calculator helps you model these variables realistically, showing how different choices affect your monthly investment.
Understanding Your Results: The calculator provides estimated monthly costs based on your inputs, breaking down expenses across the main components: AI processing, voice infrastructure, telephony, and messaging. Your results will vary depending on call patterns—brief confirmation calls cost significantly less per interaction than detailed consultations. The estimates shown represent variable operational costs only and don't include one-off setup fees, phone number rentals, or potential volume discounts that providers may offer as your usage scales. Use these figures as a planning guide to understand how different usage scenarios impact your monthly investment.
