Cartesia review

Cartesia is best known for its Sonic voice models, and its managed agents are the cheapest per minute here. The pricing page lists agent call time at $0.03 per minute, down from $0.06, with LLM usage billed separately and $0.014 per minute for calls on a Cartesia-provided number. Plans are small: Free includes $1 of agent usage a month, Pro costs $5 with $5 of prepaid agent usage and 100K speech credits, Startup $49 and Scale $299, each with prepaid agent usage equal to the plan price. Concurrency steps from 8 to 12, 20 and 60 calls across tiers, and included phone numbers rise from 1 to 10. Instant voice cloning starts on Pro and pro cloning on Startup. For a developer testing a phone agent or an agency running a few low-volume lines, the entry cost is hard to beat. The platform is thinner than Retell or Bland on campaigns, transfers and visual flow tools.

Who it is for

Developers on a tight budget who want a low agent rate and Cartesia's own voices.

Price

Free plan with $1 of agent usage a month; Pro $5 per month with $5 of agent usage; agents $0.03 per minute plus LLM.

Pro $5 /mo Select Pro 100K credits / month $5 prepaid agents / month
Quoted from the vendor pricing page on November 7, 2026.

Key features

• Managed voice agents billed at $0.03 per minute
• Text-to-speech and speech-to-text credits in every plan
• Cartesia-provisioned phone numbers, 1 to 10 by plan
• Instant voice cloning from Pro, pro voice cloning from Startup
• Evaluations free for a limited time

Strengths and weaknesses

• Strength: Lowest published agent rate in this list
• Strength: Free plan and a $5 entry plan
• Strength: Concurrency rises from 8 to 60 across paid tiers
• Weakness: LLM usage during calls is billed separately
• Weakness: Cartesia numbers add $0.014 per minute
• Weakness: Fewer builder and campaign features than Retell or Bland

Key facts

• Plans: Free, Pro $5, Startup $49, Scale $299, Enterprise
• Concurrent calls: 8, 12, 20 and 60 across plan tiers
• Telephony: $0.014 per minute on a Cartesia number

Where it ranks

Cartesia is No. 6 in our Best AI Voice Agent Platforms verdict and No. 1 in Best Text-to-Speech APIs.