Your customers don't all sound the same. Your testing shouldn't either.
Introduction
Voice AI is going global, and it's happening fast. Businesses are deploying conversational agents to handle customer calls in Arabic, Hebrew, German and Spanish, French and Hindi. But if you are on an engineering or QA team, you know the sinking feeling of discovering a blind spot too late: an agent that works flawlessly in American English can completely fall apart the moment a caller speaks Bengali with a regional accent, or switches mid-sentence between Hindi and English.
Let's be honest. Testing voice AI agents in English alone is like QA-testing a web app on a single browser and calling it production-ready. It simply doesn't reflect how real people actually talk.
That is exactly why Cekura was built. We engineered multilingual, multi-accent, and multi-personality testing into the core architecture of our platform—not as an afterthought, and not as a premium add-on.
30+ Languages. Not Just Flags on a Dropdown.
As of now, Cekura supports 32 languages with full end-to-end testing capabilities—and we are continually expanding our support as the voice AI landscape evolves. We aren't talking about surface-level UI translations. Every supported language is deeply integrated across the entire testing pipeline, from speech recognition to voice synthesis to evaluation.
Comprehensive Global Coverage
Cekura covers the major language families driving global voice AI deployments:
- European: English, French, German, Spanish, Portuguese, Italian, Dutch, Polish, Danish, Finnish, Swedish, Czech, Romanian, Slovak, Bulgarian, Greek, Hungarian, Norwegian, Ukrainian, Russian, Estonian
- East & Southeast Asian: Chinese (Simplified), Japanese, Korean, Thai, Vietnamese, Indonesian, Malay
- Middle Eastern: Arabic, Hebrew
- African: Afrikaans
- Special Mode: Multilingual (for code-switching and multi-language conversations in a single call)
Deep, First-Class Support for India
India is one of the fastest-growing markets for voice AI, with hundreds of millions of users who prefer interacting in their native language. To meet this reality, Cekura provides dedicated, first-class support for 9 Indian languages:
| Language | Code | Native Script Example |
|---|---|---|
| Hindi | hi | नमस्ते |
| Tamil | ta | வணக்கம் |
| Telugu | te | నమస్కారం |
| Bengali | bn | নমস্কার |
| Gujarati | gu | નમસ્તે |
| Kannada | kn | ನಮಸ್ಕಾರ |
| Malayalam | ml | നമസ്കാരം |
| Marathi | mr | नमस्कार |
| Punjabi | pa | ਸਤ ਸ੍ਰੀ ਅਕਾਲ |
If you are deploying a voice AI agent for a bank in Mumbai, a telecom provider in São Paulo, or a healthcare hotline in Dubai, your agent must understand and respond naturally in the local language. Cekura lets you validate that experience before your customers are the ones testing it.
Accents and Dialects: Language Alone Isn't Enough
Here is a critical reality most testing platforms miss entirely: two people can speak the exact same language and sound completely different.
A customer calling from Chennai speaks English differently than one calling from London or Lagos. A Spanish speaker from Buenos Aires has different speech patterns than one from Madrid. Cekura's personality system solves this by treating language and accent as independent, orthogonal configuration dimensions.
You can easily create highly specific test personalities, such as:
- English with an Indian accent to test how your agent handles India's 125+ million English speakers.
- Spanish with a Latin American accent to ensure your deployments work seamlessly for users across Central and South America.
- French with a Canadian accent to validate comprehension for Québécois and other Francophone Canadian callers.
Building Personalities: Not Just a Voice, but a Person
Testing a voice AI agent with a robotic, monotone test caller is like testing a car's crash safety with a mannequin that can't move. You need realistic human behavior.
Every personality in Cekura is constructed across 8 configurable dimensions, capturing how real humans actually communicate:
1. Language: Choose from our currently supported 32 languages. Greetings, idle messages, and conversational cues automatically adapt. Set a personality to Tamil, and it automatically greets with "வணக்கம்" and asks "நீங்கள் இன்னும் இருக்கிறீர்களா?" during dead air.
2. Accent: Layer regional variations over your chosen language.
3. Gender: Select Male, Female, or Neutral to affect voice selection and tonal characteristics.
4. Emotion (59 Distinct States): Powered by Cartesia Sonic-3, personalities can express 59 emotions. Test a "frustrated" customer disputing a charge versus a "cheerful" one checking a balance.
5. Speaking Speed: Real people speak at different paces. Adjust from a slow 0.8x to a rushed 1.2x.
6. Voice Volume: Fine-tune from a quiet, intimate 0.5 to a loud, assertive 2.0.
7. Interruption Behavior: Choose between Off, Low, Medium, and High. This configures over 20 underlying parameters (wait times, word-count thresholds) to simulate polite waiters and impatient interrupters alike.
8. Background Environment: Real calls don't happen in soundproof studios. Cekura includes 31 predefined background environments ranging from coffee shops and street traffic to construction sites and crying babies. Need a specific factory floor or hospital ward? Use the Custom URL option for infinite possibilities.
Combined with network simulation (packet loss, jitter, latency), you are testing your agent under the exact acoustic and network conditions it will face in production.
The Combinatorial Advantage: Exploding Your Test Coverage
Here is where Cekura fundamentally changes the economics of voice AI testing. Because each personality dimension is an independent axis, combining them with Cekura's structured, deterministic test scenarios multiplies your coverage.
The Math of Comprehensive Testing:
Imagine a single test scenario: "Customer calls to dispute a billing charge."
Cross that scenario with just 5 languages × 3 emotions × 3 speeds × 4 interruption levels × 5 background environments.
You instantly generate 900 unique test combinations.
Scale that across 20 test scenarios, and you have 18,000 structured test executions. Manually, this would take months. With Cekura, it is a single test run.
Most importantly, this behavior is deterministic. The test personality follows defined scripts, responding to specific keywords and interrupting at specific thresholds. This guarantees reproducible failures for debugging, strict regression detection after deployments, and total coverage confidence.
Under the Hood: The Technical Architecture
For engineering teams, here is how Cekura delivers reliable multilingual testing at scale:
- Intelligent Triple Speech-to-Text Pipeline: Not all STT engines are created equal. Cekura uses an intelligent tri-provider architecture, automatically routing each language to the engine that performs best for it based on extensive internal benchmarking.
- Dual Voice Synthesis Pipeline: Deliver the 59 emotion states, granular speed, volume and stability controls.
- Automated Contextual Translation: When you configure a personality's language, Cekura automatically translates conversational elements (greetings, re-engagement prompts) with appropriate cultural context, formality, and professional tone. Zero manual localization required.
Multilingual Testing Cannot Be an Afterthought
The cost of deploying broken multilingual voice AI isn't just a hit to your CSAT score. It means lost revenue from churned customers, brand damage from agents that fail to understand regional dialects, and massive compliance risks in regulated industries like banking and healthcare.
Cekura eliminates these risks by shifting multilingual validation left—catching issues in development and QA, where they are cheap and easy to fix.
Your voice AI agent will inevitably face callers speaking English with an Indian accent, French with a Canadian inflection, and Spanish with a Latin American cadence. Often, it will happen all on the same day. Cekura ensures your agent is ready for every single one of them.
Don't let your first multilingual test be a real customer call.
Ready to build agents that truly speak your customers' language?
Stop guessing and start validating. Discover how our combinatorial testing can bulletproof your voice AI against real-world linguistic diversity. Visit www.cekura.ai to explore the platform and see the product in action today!