Hindi-English Call Transcription: Why Most Speech-to-Text Tools Get It Wrong
Picture a normal sales call between a real estate agent in Ahmedabad and a prospective buyer.
It goes something like this:
"Haan sir, yeh property ka carpet area 1,200 square feet hai. Location is very prime, SG Highway se bas five minutes. Aapka budget kitna hai? We have some options in the 45 to 50 lakh range. Agar interested ho toh main kal site visit arrange kar sakta hoon."
One paragraph. Three language switches. Hindi, English, and a blend of both that linguists call code-switching and the rest of us just call "how people talk."
This is completely normal in Indian business conversations. It's not sloppy speaking. It's not a quirk. It's the default mode of communication for hundreds of millions of people. Hindi-English. Gujarati-English. Marathi-English. Tamil-English. Every region has its own flavor.
Now try running that audio through a standard transcription tool.
What Standard Transcription Produces
If you set the language to English, a typical speech-to-text engine will catch the English fragments and hallucinate the rest. You get something like:
"Hon sir, yeh property ka cup a 1,200 square feet. Location is very prime, SG highway said boss five minutes. Upka budget? We have some options in the 45 to 50 lakh range. Agar interested hotel main call site visit around car sakta hoon."
It caught "1,200 square feet" and "location is very prime" because those are English. Everything else is noise. "Cup a" instead of "carpet area." "Hotel main call" instead of "ho toh main kal." The transcription is roughly 40% accurate, which sounds bad and is actually worse than bad. Because a 40% accurate transcript isn't just incomplete. It's actively misleading.
If you set the language to Hindi, the engine flips the problem. It gets the Hindi portions right but mangles every English term. "Square feet" becomes some phonetic Hindi approximation. "SG Highway" is unrecognizable. Technical and business terms that are always spoken in English ("EMI," "carpet area," "possession date," "registry") get destroyed.
Why This Happens (Without Getting Too Academic)
Most speech recognition models are trained on monolingual data. They learn the sounds, patterns, and vocabulary of one language at a time. When you feed them audio that switches languages mid-sentence, they don't gracefully handle the transition. They try to force-fit the sounds into whichever language model is active.
Think of it like autocorrect on your phone. Type in English, it works fine. Type in Hindi (Roman script), it works okay. Start mixing both in the same sentence and autocorrect turns into a chaos machine, "correcting" perfectly valid Hindi words into nonsensical English ones.
Speech recognition has the same fundamental problem at the acoustic level. The sound patterns for Hindi vowels don't map to English vowel models. Consonant clusters that are natural in one language don't exist in the other. When the model encounters a Hindi phoneme while running in English mode, it picks the closest English sound, which is often completely wrong.
The language boundary is the hardest part. Humans switch between languages seamlessly, sometimes within a single word ("arrange kar sakta hoon" has an English verb with Hindi grammar wrapped around it). Monolingual models have no mechanism to detect this switch or adapt to it.
What Code-Switch-Aware Models Do Differently
Models built for multilingual audio take a fundamentally different approach. Instead of assuming one language and sticking with it, they're trained on audio that contains multiple languages within the same utterance.
The key differences:
Language boundary detection. The model identifies where one language ends and another begins, even when the switch happens mid-word. It doesn't wait for a sentence break or a pause.
Parallel acoustic models. Instead of one set of sound patterns, the model maintains representations for multiple languages simultaneously. When it detects a switch to English phonemes, it routes to the English acoustic model without losing context.
Shared vocabulary handling. Business terms that are always spoken in English ("EMI," "carpet area," "site visit," "budget") get special treatment. The model learns that these terms appear in Hindi sentences in their English form and should be transcribed as English regardless of the surrounding language.
Transliteration awareness. The model understands that "aapka" and "आपका" are the same word and can produce output in the script that makes sense for the context.
The result is transcription that handles the actual audio faithfully. "Carpet area" stays "carpet area" even inside a Hindi sentence. "Kal site visit arrange kar sakta hoon" is transcribed accurately with both the English nouns and the Hindi grammar intact.
Why This Matters Beyond Accuracy Numbers
If transcription is just a text file people read, 60% accuracy is annoying but survivable. You can squint at the garbled output and guess what was said.
But if you're building analytics on top of transcription (which is the whole point of call intelligence), inaccurate transcription breaks everything downstream. This is why transcription accuracy is the foundation of every feature SalesEar provides.
Sentiment analysis reads the wrong words. If "interested" gets transcribed as "intrusted" and "happy" becomes "heppy," the sentiment model can't work with the input it's given.
Objection detection misses objections spoken in Hindi. The customer says "budget thoda kam hai" (budget is a bit low) and the system doesn't register it because the Hindi portion was garbled. You have an objection tracking feature that systematically misses objections from Hindi-speaking customers.
Call scoring penalizes agents for phantom problems. The agent said the right things, but the transcript captured them wrong. The scoring model docks points based on text that doesn't reflect what was actually said.
Keyword tracking is language-blind. You set up tracking for "site visit" but the agent said "site visit arrange karte hain" and the transcription engine butchered the surrounding Hindi, so the keyword detection doesn't fire because the context is garbled.
The accuracy of your transcription is the ceiling for every piece of analysis built on top of it. 60% transcription accuracy means your analytics can never be better than 60% accurate either. Transcription accuracy matters most when you're trying to review calls at scale without listening to each one manually.
The Indian Market Specifics
This isn't just a Hindi-English problem. Indian business conversations happen in dozens of language combinations, and every region has its own pattern.
Gujarat: Gujarati base with English business terms and occasional Hindi. A broker might say "aa property ni price 48 lakh chhe, carpet area 1,100 square feet, and possession December 2026 ma malse."
Maharashtra: Marathi with English and Hindi mixed in, especially in Mumbai where all three languages coexist in a single conversation.
South India: Tamil-English, Telugu-English, Kannada-English. The code-switching patterns are different (English technical terms inside Dravidian grammar) but the transcription challenge is the same.
Any solution that only handles Hindi-English is solving a fraction of the problem for a fraction of the market. SalesEar supports all of these combinations. See the full multilingual call analytics breakdown.
For real estate teams dealing with Gujarati-English and Hindi-English calls daily, see how brokerages are using call analytics to improve follow-up conversion.
What to Look for in a Transcription Tool
If you're evaluating transcription for Indian business audio, the three questions that matter:
Can it handle language switches within a sentence? Not just "this call is in Hindi" vs "this call is in English." Within a single sentence, does it maintain accuracy when the language changes?
Does it preserve English business terms inside non-English sentences? "EMI," "possession," "carpet area," "site visit" should always come through in English regardless of the sentence language.
Has it been tested on your specific language combination? Hindi-English accuracy doesn't guarantee Gujarati-English accuracy. The phonetic patterns are different. Ask for sample outputs in your team's actual language mix.
If you want to test this with your own call recordings, SalesEar handles code-switched Indian language audio out of the box. See how it works, upload a few recordings, and see the difference. salesear.com/signup