Question 1

Do TTS, STT, and Agent concurrency limits affect each other?

Accepted Answer

No. Each service has its own dedicated concurrency pool, so using TTS won’t impact your STT or Agent concurrency. You can run them all in parallel without sharing capacity.

Question 2

How do model credits and voice agent rates work within each plan?

Accepted Answer

Your monthly plan gives you both credits for voice models AND dollars for Line Voice Agents:

Credits for voice models: each plan includes a monthly pool of credits you can use for STT and TTS at their respective rates.

Prepaid dollars for voice agents: during the Line launch period, in addition to credits for voice models, you also now get prepaid dollars per month to use towards voice agents at no additional cost.

For example, the Scale plan, at $299/month, gives you 8M credits/month to use on STT or TTS models. On top of these 8M credits/month, you ALSO get $299/month to spend on Line Voice Agents. The free plan has $1/mo of prepaid dollars to use towards voice agents. Enterprise plans will have custom pricing.

Question 3

How many Line voice agent minutes do I get per plan?

Accepted Answer

At a competitive $0.06/minute, these are the approximate agent call minutes per plan:

Free Plan - 17 minutes.

Pro Plan - 1 hour, 23 minutes.

Startup Plan - 13 hours, 37 minutes.

Scale Plan - 83 hours, 3 minutes.

Note that these calculations do not include the costs for fully managed phone numbers. Please take these into account if you opt in.

Question 4

How many credits do I need?

Accepted Answer

Sonic text-to-speech: One minute of audio generation requires 750-800 credits. 1 credit equals 1 character. This excludes Pro Voice Cloning.

Ink speech-to-text: One hour of audio is only $0.39 on the Scale plan. 3 credits equals 1 second of audio.

Question 5

How many credits do I need for Pro Voice Cloning?

Accepted Answer

It costs 1M credits to train one Professional Voice Clone. Each character of TTS using a Professional Voice Clone will cost 1.5 credits.

Question 6

What happens to my rollover credits if I change my pricing tier?

Accepted Answer

You’ll keep all the credits you’ve already paid for when switching tiers.

Existing credits remain: Nothing is lost when you upgrade or downgrade.

New rollover limit applies: Your rollover cap resets to 2x your new monthly plan rate.

Once your balance drops below this cap, future credits will continue rolling over up to the new limit.

Question 7

What happens if I upgrade to a higher subscription tier?

Accepted Answer

You will automatically get the amount of credits you paid for on that new tier added to your current credit balance! With rollovers, you can accrue up to 2x your monthly rate.

Question 8

What if I cancel or downgrade my tier in the middle of a payment period?

Accepted Answer

You will keep the credits in your account until you use them. Your account will remain in the same tier until the end of that period, at which time you will automatically be downgraded to the selected tier.

Question 9

When does my subscription renew?

Accepted Answer

Your subscription will renew monthly from your purchase date. If you purchase on March 31, it will renew on April 30, May 31, etc...

Question 10

What happens if I use more model credits than I have in my account?

Accepted Answer

Paid users can turn on overages to go negative into their credit balance. Your overage rate will vary by your subscription tier.

At pro tier, it's $65 per 1M credits. At startup tier, it's $45 per 1M credits. At scale tier, it's $38 per 1M credits.

If your overages are off, new requests will be blocked if all your credits have been consumed.

Question 11

What happens if I use more prepaid voice agent dollars than I have in my account?

Accepted Answer

You will continue paying at the same rate as your plan for voice agents.

Question 12

How and when are overages charged?

Accepted Answer

This usage-based overage charge will begin incurring once you exceed the limit included in your plan.

Question 13

How are break tags counted in billing?

Accepted Answer

Each break tag is counted as 1 credit in the transcript of a TTS request.

Question 14

Is Cartesia SOC 2 Type II certified?

Accepted Answer

Yes, Cartesia is SOC 2 Type II certified.

Question 15

Can I deploy the models on-premise or in a virtual private cloud?

Accepted Answer

Yes, reach out to our sales team so we can best understand your needs.

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