Pricing comparison

Voice AI platforms,
line item by line item.

Compare Speko, Vapi, Bland AI, Retell AI, and Cartesia Line using the parts of the bill each product actually includes. Platform, models, telephony, subscriptions, and other charges are separated below.

Start with 100 free minutes See Speko pricing

First, classify the product

These prices measure different layers.

Speko is a voice AI platform with one API for the full voice stack. Vapi is a voice-agent platform with separately billed providers. Bland AI focuses on phone automation. Retell AI assembles a phone-agent rate from selected components. Cartesia sells model APIs and a separate full-agent product called Line.

Voice AI platform

Speko

One API and one connected-minute rate for the full voice stack.

Voice agent platform

Vapi

Managed orchestration with a provider stack that the developer configures.

Phone automation platform

Bland AI

Tiered plans for phone automation, with lower minute rates at paid tiers.

Voice agent platform

Retell AI

A component-based phone-agent bill assembled from infrastructure and usage choices.

Voice agent platform and model APIs

Cartesia Line

Line is Cartesia's full voice-agent platform; Sonic and Ink are separate model APIs.

Pricing side by side

What each rate includes.

Checked against official sources

Swipe or scroll horizontally to compare every charge.

Voice AI platform pricing separated into platform, model, telephony, subscriptions, and other charges.
Product Base per-minute charge Model and provider costs Telephony Subscriptions and other charges
Speko Voice AI platform Included in the $0.09/min connected-minute rate. STT, LLM, and TTS are included. Inbound and outbound telephony are included.

$2/phone number/month. No platform fee. First 100 minutes are free.

Speko pricing
Vapi Voice agent platform $0.05/min for Vapi hosting and orchestration. STT, LLM, and TTS are pass-through charges, or connect your own provider keys and pay those providers directly. Billed separately by the connected telephony provider.

10 concurrent calls included, then $10/additional concurrent call/month.

Vapi pricing Vapi pricing FAQ
Bland AI Phone automation platform Start $0.14/min; Build $0.12/min; Scale $0.11/min. LLM, STT, and TTS are included in the connected-minute rate. Telephony is separate. Bland telephony has a $0.015 minimum charge per outbound attempt, including failed calls. Transfers on Bland numbers add $0.05, $0.04, or $0.03/min by tier; BYOT transfers are free.

Start $0/month; Build $299/month; Scale $499/month.

Bland AI pricing Bland AI billing docs
Retell AI Voice agent platform Base voice infrastructure is $0.055/min. TTS and LLM charges are added by model choice. The published $0.07-$0.31/min range is composite, not a platform fee. Custom SIP is $0; the listed US carrier option is about $0.015/min.

20 concurrent calls included, then $8/additional concurrent call/month.

Retell AI pricing
Cartesia Line Voice agent platform and model APIs Line call duration is $0.06/min. LLM usage is a separate component. LLM use for agents created in the Cartesia UI is free for a limited promotional period. Using a Cartesia-provided phone number adds $0.014/min.

Free $0/month includes $1 in prepaid Line agent usage; Pro $5 includes $5, Startup $49 includes $49, and Scale $299 includes $299. Separate model credits, agent slots, and concurrency also vary by plan.

Cartesia pricing Cartesia Line introduction Cartesia Line integrations

Prices are public list prices in USD. Taxes, custom enterprise contracts, and optional features are not included. Vendor prices can change after the verification date.

Do the same math

Build an apples-to-apples estimate.

A published headline rate can cover one line item or the whole stack. Use one call profile and include every charge before comparing totals.

  1. 01

    Estimate connected minutes and include any attempt-based minimum charges.

  2. 02

    Add the platform or orchestration rate.

  3. 03

    Add STT, LLM, and TTS usage when they are not included.

  4. 04

    Add carrier, SIP, phone-number, and transfer charges.

  5. 05

    Add concurrency, subscription, and optional feature fees.

  6. 06

    Subtract included or prepaid usage credits before estimating overage.

  7. 07

    Run the same call mix through every calculation.

Selection guide

Match the product to the system you need.

This is a classification guide, not a universal ranking. The relevant choice depends on which layer your team wants to own.

One API and one price for the full voice stack Speko

The $0.09/min connected-minute rate includes STT, LLM, TTS, telephony, and routing.

See Speko pricing A provider stack you select and configure Vapi

Vapi charges for orchestration, then passes through or connects your chosen providers.

Open official source Tiered plans centered on phone automation Bland AI

Bland combines LLM, STT, and TTS in a connected-minute rate with paid monthly tiers.

Open official source A component calculator for a phone-agent stack Retell AI

Retell assembles a rate from base voice infrastructure and the models and telephony selected.

Open official source Cartesia model APIs or the Line agent layer Cartesia

Cartesia sells Sonic and Ink model APIs as well as Line, its full voice-agent platform.

Open official source

Questions

Voice AI pricing FAQ.

Which voice AI platform has the lowest price?

There is no honest answer without a stack and usage profile. Vapi lists orchestration separately from models and telephony. Retell builds a composite rate from selected components. Bland combines models with a tiered connected-minute rate but handles telephony separately. Cartesia Line separates call duration, telephony, and standard LLM use. Speko lists one connected-minute rate for STT, LLM, TTS, telephony, and routing.

Why is Vapi at $0.05 per minute not directly comparable to Speko at $0.09?

Vapi's $0.05/min rate covers hosting and orchestration; STT, LLM, TTS, and telephony are separate. Speko's $0.09/min rate includes those four components plus routing. Compare the same line items before comparing the totals.

Does Retell AI cost $0.07 per minute?

Retell publishes a $0.07-$0.31/min range built from multiple components. Its base voice infrastructure is $0.055/min, then TTS, LLM, telephony, and optional features depend on the selected configuration.

How do Retell AI and Vapi pricing differ?

Vapi lists a $0.05/min hosting and orchestration charge. Model usage is pass-through or BYOK, and telephony is billed separately. Retell starts with $0.055/min for Voice Infra, then adds the selected TTS, LLM, telephony, and optional features.

What are alternatives to Vapi and Bland AI?

Retell AI, Cartesia Line, and Speko are other voice-agent platforms with different billing structures. Retell uses component pricing, Cartesia Line separates call duration and telephony, and Speko publishes one connected-minute rate for STT, LLM, TTS, telephony, and routing.

Is Cartesia only a text-to-speech provider?

No. Cartesia offers Sonic and Ink model APIs, and it also offers Line, a full voice-agent platform. Line pricing should be evaluated separately from Cartesia model API pricing.

What is included in Speko pricing?

Speko is $0.09 per connected minute, including STT, LLM, TTS, telephony, and routing. The first 100 minutes are free. Phone numbers are $2 each per month.

How current are these voice AI prices?

Every price on this page was checked against the vendor's official pricing or documentation on July 23, 2026. Vendor pricing changes, so follow the cited source before making a purchasing decision.

Source ledger

Every number links to the vendor.

No reseller summaries or third-party calculators are used. All sources below are first-party pricing pages or product documentation.

Speko

Vapi

Bland AI

Retell AI

Cartesia Line

Keep researching: Speko pricing Head-to-head comparisons Public voice benchmarks Developer docs

Speko

One API. One connected-minute rate.

Build with STT, LLM, TTS, telephony, and routing included. Start with 100 free minutes and no card.

Build an agent Read the docs