Voice AI Cost Tracking: Real-Time Billing Insights

Complete Visibility Into Every Dollar of Your Voice AI Spend

Ask any CFO what keeps them up at night about AI adoption, and they'll mention runaway costs. Voice AI compounds this concern because costs accumulate across multiple services simultaneously: LLM inference, speech-to-text, text-to-speech, and telephony. Each call generates charges across four different billing dimensions.

Without granular cost tracking, finance teams are left guessing. Monthly bills arrive with aggregate totals but no insight into which assistants drive costs, which campaigns deliver ROI, or where optimization opportunities exist.

Burki was built by operators who understand this pain. Our voice AI cost tracking system provides real-time visibility into every cent of your voice AI spend, broken down by call, assistant, campaign, and service type. No more billing surprises. No more black-box invoices.

The Per-Call Cost Breakdown: Total Transparency

Every call on Burki generates a complete cost breakdown the moment it ends. This is not an estimate or approximation. It is the actual cost calculated from real usage data.

What You See for Every Call

When you open any call record in the Burki dashboard, you will find a cost breakdown section displaying:

This granularity matters because it reveals where your money actually goes. A support assistant handling simple queries might show high telephony costs relative to LLM costs, indicating callers are spending time on hold or navigating menus. A sales assistant closing deals might show elevated LLM costs from complex reasoning and persuasion responses.

Token-Level LLM Tracking

LLM costs are tracked at the token level, separating input tokens (what the AI reads) from output tokens (what the AI generates). This distinction matters because:

• Input tokens are typically cheaper (often 2-4x less than output tokens)
• Bloated system prompts inflate input costs on every turn
• Verbose AI responses drive up output costs

The dashboard shows token counts alongside costs, enabling direct optimization. If you notice an assistant with unusually high input token costs, you can examine the system prompt for unnecessary length or redundant context.

Per-Character TTS Tracking

Text-to-speech costs are calculated per character synthesized. The dashboard displays:

• Total characters spoken by the AI
• TTS provider and model used
• Cost per character at current pricing
• Total TTS cost for the call

This visibility reveals when AI responses are too verbose. An assistant that provides lengthy answers when brief ones suffice will show elevated TTS costs. The data enables targeted prompt optimization.

Per-Minute STT Tracking

Speech-to-text costs are calculated based on audio duration transcribed. You see:

• Total audio minutes from the caller
• STT provider and model used
• Cost per minute at current pricing
• Total STT cost for the call

Long pauses, background noise, and caller verbosity all extend STT costs. The data helps identify calls where callers ramble excessively or where silence detection could be tuned.

The Real-Time Tracking Dashboard

Burki's cost tracking dashboard is designed for finance and operations professionals who need immediate answers to spend questions.

Dashboard Statistics Overview

The main dashboard provides at-a-glance cost metrics:

Time-Based Views:

• Today's total spend
• This week's spend
• This month's spend
• All-time cumulative spend

Performance Metrics:

• Cost per call (average)
• Cost per minute (effective rate)
• Cost per successful outcome
• Cost variance from previous period

Trend Visualization:

• Daily cost charts
• Component breakdown over time
• Cost per assistant trends
• Campaign cost performance

Filtering and Drill-Down

The dashboard supports extensive filtering to answer specific questions:

Filter by Time Range:

• Preset ranges (today, yesterday, last 7 days, last 30 days)
• Custom date range selection
• Hour-by-hour analysis for recent periods

Filter by Assistant:

• View costs for specific assistants
• Compare assistant performance
• Identify cost outliers

Filter by Campaign:

• Track campaign-specific spend
• Calculate cost per contact reached
• Measure campaign ROI

Filter by Provider:

• See costs by LLM provider (OpenAI, Anthropic, etc.)
• Compare TTS provider costs
• Analyze telephony carrier charges

The Call List with Cost Column

The call history view includes cost data inline:

Clicking any row opens the full call details, including the complete cost breakdown, transcript, and recording.

Cost Allocation by Assistant and Campaign

Understanding aggregate costs is useful. Understanding where those costs come from is actionable.

Assistant-Level Cost Analytics

For each assistant, Burki tracks:

Usage Metrics:

• Total calls handled
• Total minutes of conversation
• Average call duration
• Success rate

Cost Metrics:

• Total cost attributed to this assistant
• Average cost per call
• Cost breakdown by service type
• Cost trend over time

Efficiency Metrics:

• Cost per successful outcome
• Cost per minute of talk time
• LLM cost as percentage of total
• TTS cost as percentage of total

This enables direct comparison between assistants. If your sales assistant costs $0.06 per call while your support assistant costs $0.03 per call, you can investigate whether the difference is justified by outcome value or represents an optimization opportunity.

Campaign Cost Attribution

For outbound campaigns, cost tracking is critical for ROI calculation. The campaign analytics dashboard shows:

Campaign Summary:

• Total contacts in campaign
• Contacts reached
• Successful outcomes
• Total campaign cost

Per-Contact Economics:

• Cost per dial attempt
• Cost per connection
• Cost per successful outcome
• Cost per conversion (if tracked)

Campaign Comparison:

• Side-by-side campaign cost analysis
• Cost efficiency rankings
• Trend analysis across campaigns

With this data, you can calculate true customer acquisition cost (CAC) for voice AI outreach campaigns and compare against other channels.

Organization-Wide Allocation

For organizations with multiple teams or business units, cost allocation matters for internal chargebacks. Burki enables:

• Tagging assistants by department or cost center
• Exporting costs grouped by tags
• Setting up allocation reports for accounting

Alerts and Budget Controls

Real-time tracking is valuable. Proactive alerts prevent budget overruns before they happen.

Wallet System with Balance Monitoring

Burki operates on a prepaid wallet system. Your organization maintains a wallet balance, and costs are deducted in real-time as calls occur.

Wallet Dashboard Shows:

• Current available balance
• Reserved balance (for calls in progress)
• Recent transactions
• Low balance warnings

Real-Time Balance Monitoring: During active calls, the system continuously monitors your wallet balance. If balance approaches zero, the system can:

• Alert administrators in real-time
• Send email notifications
• Gracefully end calls before hard cutoff
• Queue pending outbound campaigns

Auto Top-Up Configuration

For organizations that want hands-free balance management:

Auto Top-Up Settings:

• Threshold balance: Trigger amount (e.g., $50)
• Top-up amount: How much to add (e.g., $200)
• Maximum top-ups per period: Safety limit
• Payment method: Stripe integration

When your balance drops below the threshold, the system automatically charges your payment method and adds funds. You receive email confirmation of every auto top-up.

Budget Alerts

Set proactive alerts at the organization level:

Alert Types:

• Daily spend threshold reached
• Weekly spend threshold reached
• Monthly spend threshold reached
• Single-call cost exceeds limit
• Assistant cost exceeds limit

Alert Channels:

• Email notifications
• Dashboard notifications
• Webhook delivery (for integration with Slack, PagerDuty, etc.)

Per-Campaign Budget Limits

For outbound campaigns, set hard budget caps:

• Maximum total campaign spend
• Maximum cost per contact
• Automatic pause when limit reached
• Alert before limit is hit

This prevents a misconfigured campaign from burning through your entire budget overnight.

Export and Reporting

Finance teams need data in their systems. Burki supports comprehensive export capabilities.

Export Formats

Call-Level Export:

• CSV export of all calls with cost breakdown
• JSON export for programmatic processing
• Customizable columns and date ranges

Export Fields Available:

• Call timestamp
• Call duration
• Caller phone number
• Assistant used
• Campaign (if applicable)
• LLM cost
• TTS cost
• STT cost
• Telephony cost
• Total cost
• Call status
• Outcome data

Monthly Statements

At the end of each billing period, Burki generates a comprehensive statement:

Statement Contents:

• Summary of total spend
• Breakdown by service type
• Platform fees vs pass-through costs
• Managed fees (Burki Cloud mode)
• BYO costs (when applicable)
• Number management fees
• Daily usage chart
• Top assistants by cost
• Top campaigns by cost

Statements are available in PDF format and downloadable from the dashboard.

Ledger System for Audit Compliance

For organizations with strict audit requirements, Burki maintains an append-only ledger of all financial transactions:

Ledger Entry Types:

• Top-up: Funds added to wallet
• Charge: Usage deduction
• Refund: Credits returned
• Adjustment: Manual corrections
• Grant: Free credits applied

Every ledger entry includes timestamp, amount, description, and balance after transaction. The ledger cannot be modified, only appended. This provides a complete audit trail for financial compliance.

API Access for Cost Data

For organizations that need programmatic access to cost data:

GET /api/v1/calls?include_costs=true
GET /api/v1/analytics/costs?start_date=2026-01-01&end_date=2026-01-31
GET /api/v1/billing/ledger
GET /api/v1/billing/statements

This enables integration with:

• Business intelligence tools
• Custom dashboards
• Accounting systems
• Cost anomaly detection systems

BYO Mode: Maximum Cost Control

Burki offers two billing modes that affect how costs are tracked and charged.

Burki Cloud Mode (Managed)

In managed mode, Burki provides all API keys and handles provider relationships:

• You pay a single unified rate
• Costs include pass-through provider fees plus 15% markup
• Simplified billing with one vendor
• No provider account management required

BYO Mode (Bring Your Own)

In BYO mode, you bring your own API keys for providers:

• Direct provider costs (no markup)
• Platform fee only to Burki
• Full visibility into provider-level costs
• Volume discounts from providers apply

BYO Supported Providers:

• LLM: OpenAI, Anthropic, Google, Azure
• TTS: ElevenLabs, Deepgram, Cartesia, OpenAI
• STT: Deepgram
• Telephony: Twilio, Telnyx, Vonage

BYO mode provides maximum cost control for organizations that want direct provider relationships and the ability to negotiate enterprise rates.

Frequently Asked Questions

How quickly do call costs appear in the dashboard?

Call costs are calculated and displayed within seconds of call completion. The cost breakdown is available immediately in the call detail view and reflected in dashboard totals in real-time.

Can I set different budgets for different assistants?

Currently, budget alerts and limits are set at the organization and campaign level. Per-assistant budget limits are on our roadmap. However, you can track per-assistant costs in the analytics dashboard and set up custom alerts via webhook integration.

How are costs calculated for calls that fail or are abandoned?

You are only charged for actual usage. If a call fails to connect, you incur minimal or zero cost. For abandoned calls, you are charged for the duration of actual conversation. STT, TTS, and LLM costs are calculated based on actual usage during the call.

Can I export cost data for tax purposes?

Yes. Monthly statements provide a complete record of all charges and are suitable for tax documentation. The append-only ledger system provides an audit-ready transaction history. Statements are available in PDF format.

How does cost tracking work with the trial credits?

Trial credits (200 minutes for new signups) are tracked and deducted the same way as paid balance. The dashboard shows trial credit usage alongside paid balance. You can see exactly how your trial minutes are being consumed.

What happens if my wallet balance reaches zero during a call?

The system monitors balance in real-time during calls. Before balance reaches zero, the system will gracefully end ongoing calls (with a brief warning message to callers if configured) and pause any pending outbound campaigns. This prevents hard cutoffs mid-sentence.

Can I get historical cost data for calls from months ago?

Yes. All cost data is retained indefinitely. You can export call costs from any time period and generate reports on historical spend. The ledger maintains a complete financial history from account creation.

How do I know if I should switch from Burki Cloud to BYO mode?

BYO mode typically makes sense when:

• You have significant volume (10,000+ minutes/month)
• You already have enterprise agreements with providers
• You have prepaid credits with providers to use
• You want maximum cost visibility and control

The dashboard shows your cost breakdown by service type, making it easy to calculate whether BYO mode would reduce your costs.

Take Control of Your Voice AI Costs

Voice AI should not be a financial black box. With Burki's comprehensive cost tracking system, you get:

• Per-call cost breakdown (LLM, TTS, STT, telephony)
• Real-time dashboard with filtering and drill-down
• Cost allocation by assistant and campaign
• Proactive alerts and budget controls
• Export capabilities for finance and audit
• Append-only ledger for compliance

Every cent is accounted for. Every dollar is attributable. Every optimization opportunity is visible.

Ready to see exactly where your voice AI spend goes?

Start your free trial with 200 minutes and full access to our cost tracking dashboard. No credit card required. See your costs in real-time from day one.

Burki is SOC 2 Type II certified and HIPAA compliant at no extra cost.