Cartesia

Cartesia's Sonic model is one of the fastest TTS APIs available, with time-to-first-audio around 40ms — purpose-built for real-time voice agents where latency dominates the experience. It bills per character on usage-based credits, offers instant voice cloning on paid plans, and keeps a small permanently-free tier for prototyping.

• ~40ms time-to-first-audio, among the lowest for production TTS.
• Streaming-first design tuned for conversational voice agents.
• Instant voice cloning available on paid plans.
• Keep in mind: Usage-based billing makes costs less predictable at variable volume.

• Text-to-speech and voice generation: Cartesia applies this capability to Realtime TTS, Voice agents workflows so users can move faster while keeping output quality reviewable.
• Voice cleanup and noise reduction: Cartesia applies this capability to Realtime TTS, Voice agents workflows so users can move faster while keeping output quality reviewable.
• Music and sound creation: Cartesia applies this capability to Realtime TTS, Voice agents workflows so users can move faster while keeping output quality reviewable.
• Transcription, dubbing, and translation: Cartesia applies this capability to Realtime TTS, Voice agents workflows so users can move faster while keeping output quality reviewable.
• Podcast and meeting audio workflows: Cartesia applies this capability to Realtime TTS, Voice agents workflows so users can move faster while keeping output quality reviewable.

• Open the official website and create a project or recording workspace. Keep a human review step in the workflow for facts, privacy, rights, and brand fit.
• Choose voice, music, enhancement, transcription, or meeting mode. Keep a human review step in the workflow for facts, privacy, rights, and brand fit.
• Upload audio or enter text, style, language, speaker, and quality requirements. Keep a human review step in the workflow for facts, privacy, rights, and brand fit.
• Preview results, adjust timing, voice, pronunciation, or cleanup strength. Keep a human review step in the workflow for facts, privacy, rights, and brand fit.
• Export audio, transcript, notes, or shareable links for publishing or collaboration. Keep a human review step in the workflow for facts, privacy, rights, and brand fit.

• Cartesia offers a free tier or trial, so you can evaluate it before upgrading.
• Paid plans for Cartesia start at about $5/mo, with higher tiers unlocking more usage, stronger models, and team features.
• Free tier (~10k characters/mo); paid plans from $5/mo (100k chars) to $299/mo (8M chars); Enterprise custom. Billed per character on credits.
• Pricing last checked 2026-06-12, source: https://www.cartesia.ai/pricing. Plans can change, so confirm on the official site.

• Voiceovers for ads, courses, and product videos. Cartesia can shorten preparation time, create first drafts, or help teams compare options faster.
• Podcast enhancement, transcription, and repurposing. Cartesia can shorten preparation time, create first drafts, or help teams compare options faster.
• Music demos, songs, and creative audio experiments. Cartesia can shorten preparation time, create first drafts, or help teams compare options faster.
• Meeting notes, call summaries, and searchable recordings. Cartesia can shorten preparation time, create first drafts, or help teams compare options faster.
• Dubbing, localization, and accessibility content. Cartesia can shorten preparation time, create first drafts, or help teams compare options faster.

• Podcasters and audio producers. If Realtime TTS, Voice agents tasks appear often in your work, Cartesia can become part of a repeatable productivity workflow.
• Video creators and educators. If Realtime TTS, Voice agents tasks appear often in your work, Cartesia can become part of a repeatable productivity workflow.
• Marketing and localization teams. If Realtime TTS, Voice agents tasks appear often in your work, Cartesia can become part of a repeatable productivity workflow.
• Meeting-heavy teams and customer operations. If Realtime TTS, Voice agents tasks appear often in your work, Cartesia can become part of a repeatable productivity workflow.
• Musicians and creative experimenters. If Realtime TTS, Voice agents tasks appear often in your work, Cartesia can become part of a repeatable productivity workflow.