Summary: Firecrawl’s 2026 comparison frames AI voice-agent selection around six stack layers, deployment control, task completion, and cost per resolved call rather than headline minute pricing. It reports that a $0.05 platform minute can become $0.13 after other voice-stack costs, making a six-minute call cost $0.78.
Speech recognition stitched to rule-based replies is no longer what a voice agent amounts to. This generation carries a conversation forward, reaches for tools, and finishes the job while the caller is still on the line. The trouble is that the market holds plenty of platforms that look alike, and the price per minute on the pricing page is a poor guide to what it costs you to resolve a call.
What you are actually assembling
Six parts have to work in concert inside an AI voice agent: telephony or real-time transport, speech-to-text with turn detection, a language or speech-to-speech model, tools and business logic, text-to-speech, and state with guardrails and observability. A vendor may bundle several of those layers, or hand the rest back to you to wire up.
Firecrawl’s 2026 look at ten platforms makes that split plain. Retell AI delivers the entire phone-agent package — visual call flows, custom functions — at $0.07–$0.31 per minute. Vapi heads the other direction: $0.05 per minute covers orchestration alone, with speech, model, and phone charges billed separately or brought by you. ElevenLabs opens free with 15 minutes and paid plans starting at $6 per month, though the language model and telephony sit outside that price.
Latency is a product decision, not a spec
Response latency covers the whole gap between the caller ending a turn and the first agent audio. Firecrawl’s evaluation guidance puts peak human turn transitions inside 200ms and calls sub-500ms agent responses responsive enough. The figure on its own says little, though: it plays out through barge-in, through false interruptions caused by background noise, and through protected speech such as legal disclaimers that has to run uninterrupted.
Choosing a platform also settles how much command you hold over those behaviors. A composable option such as Vapi or LiveKit puts models and telephony in engineering’s hands, at the cost of maintaining more of the system yourself. A packaged option such as Retell or Bland shifts that work onto the vendor, which suits teams whose main job is editing prompts and call flows.
What it can do counts for more than a feature list
The value of a voice agent lives in the work it performs behind the scenes. Firecrawl’s task-completion framework sets out three checks: a successful write that gets confirmed after the system responds, input coverage across names, addresses, and amounts in each supported language, and a failure path that avoids false confirmations and duplicate updates. Debugging an agent calls for one timeline that ties together audio, transcript, model response, tool call, tool result, and transfer.
Here the build versus buy tradeoff turns concrete. A team already anchored in a voice stack can build its workflow on ElevenLabs. A team wanting conversation design shared across chat and voice can take Voiceflow’s visual builder. Large contact centers facing procurement and governance demands are better served by managed deployments such as Synthflow or PolyAI.
The cost that matters is per resolved call
Firecrawl’s cost breakdown is the most valuable stretch of the comparison. What a platform advertises per minute may pay for a single layer of the stack. Add the voice stack, call outcomes, and operations together and a $0.05 platform minute becomes $0.13, putting a six-minute call at $0.78. Total cost divided by resolved calls is the metric to judge by, measured against what the same task costs you today.
A broader pattern in AI product building runs underneath this: the OpenAI flywheel describes how stronger models, cheaper compute, and wider reach compound. Voice agent platforms are on a comparable trajectory, and that compounding only arrives if you track full cost per resolved call rather than the headline rate.
Where to start
Teams that need to ship fast without running real-time infrastructure should begin with a packaged self-serve platform such as Retell or Bland. Teams with voice inside the product and engineering wanting the controls should look at Vapi or LiveKit. Teams already on Twilio Voice will find ConversationRelay the natural fit. The supplied comparison leaves out enterprise pricing and implementation detail for a number of platforms, so public rates are a starting point for your own cost modeling, nothing more.