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Kathana Language DataVerified4.6(2) IndiaDemo listing

RLHF preference labeling and human annotation in Indian languages

Native-speaker annotators for RLHF preference ranking, response rating, classification and entity tagging in 22 Indian languages, with gold checks and agreement reports.

Annotated and labeled dataLLM training dataData service Free sample Well documented
from $0.06 per classification label

Spec sheet

Data service ยท Listing updated 11 Nov 2026

Coverage
1 country

Show the country
Asia (1)

India

Service type
Data labeling and annotation
Typical turnaround
Pilot in 5 days, then 2โ€“6 weeks per batch
Volume

1,800 annotators; up to 250,000 preference comparisons a month

Suitable for

Startups, Mid-market, Enterprises

Delivery methods
  • Amazon S3
  • Google Cloud Storage
  • REST API
  • Manual file delivery
Formats
  • JSON Lines
  • CSV
Data source

Buyer-supplied prompts and model outputs, labelled by Kathana's employed annotators

Collection method

Guideline calibration, hidden gold questions, 10% double annotation and senior review

Overview

A managed annotation team for model builders who need human judgement in Indian languages, not machine-translated English guidelines.

What's included

  • Pairwise and ranked preference judgements on model responses, with written rationales
  • Response rating against your rubric for helpfulness, accuracy, safety and tone
  • Text classification, named-entity tagging and transcription review
  • Guideline localisation and a calibration round before production starts
  • Per-batch quality report with gold-question accuracy and inter-annotator agreement

How buyers use it

  • Reward-model and DPO training data for Indic and multilingual assistants
  • Safety red-teaming and evaluation in regional languages
  • Labelled sets for intent detection and entity extraction in customer-service bots
  • Human evaluation of machine translation and summarisation

Coverage and methodology

Kathana employs 1,800 trained annotators, including graduates in law, medicine and engineering for expert tasks, and works inside your annotation tool or its own. Each project starts with a five-day pilot of up to 2,000 items. Production batches include hidden gold questions, 10% double annotation and senior review of disagreements; typical agreement reaches a Cohen's kappa of 0.7 or higher on preference tasks. Prompts and outputs you send stay in an isolated workspace, are not reused for other clients and are deleted at project close. You own the resulting labels and may use them for model training and commercial products.

Data dictionary

11 fields as documented by Kathana Language Data.

FieldTypeDescriptionExample
item_idstringIdentifier of the labelled itemโ€”
task_typestringpreference, rating, classification, ner or transcription_reviewโ€”
languagestringISO 639-3 language codeโ€”
promptstringPrompt supplied by the buyerโ€”
response_astringFirst model responseโ€”
response_bstringSecond model responseโ€”
preferred_responsestringa, b or tieโ€”
rationalestringAnnotator's written reasonโ€”
annotator_idstringPseudonymous annotator identifierโ€”
agreement_scorenumberAgreement with other annotators on the itemโ€”
review_statusstringaccepted, corrected or escalatedโ€”

Sample

Free sample available on request

The provider sends a sample file so you can test fit and quality before you buy.

Request a sample

Pricing

Prices in USD, as published by Kathana Language Data

  • Per record

    per preference comparison

    from $2.50
  • Per record

    per classification label

    from $0.06
  • One-off purchase

    pilot of up to 2,000 items

    from $6,000

Converted amounts use DataStoa display rates and are approximate. Kathana Language Data quotes the final price, taxes and terms.

Request detailed pricing

Coverage

1 country.

Asia

1 country
  • India

Time coverage: 2017 to present.

Quality

Provider-reported

AccuracyShare of records the provider has checked as correct.
95%

Latency: Agreement and gold accuracy reported for every batch

DataStoa has not audited these figures. Ask the provider how they are measured, or test them on a sample.

Licensing and usage rights

The licence is agreed directly between you and Kathana Language Data. This summary is provider-reported; the linked terms prevail.

  • AI / ML model training
  • Use in commercial products

Not listed: internal analytics, AI retrieval and grounding, redistribution allowed, marketing and outreach, research use. Ask Kathana Language Data if you need any of these.

About Kathana Language Data

Kathana Language DataVerified provider

Licensed Indic speech and text data for AI, from consented contributors

Kathana Language Data builds speech and text datasets for Indian languages with a network of more than 40,000 consented contributors and in-house linguists in Pune and Hyderabad. AI teams license its corpora and commission annotation, RLHF and custom collection projects for ASR, TTS and language models.

Also available on: AWS Data Exchange, Databricks Marketplace

Typical reply time
Within 6 hours
Response rate
90%
Certifications
ISO 27001, SOC 2
Privacy compliance
India DPDP, GDPRProvider-reported

Reviews

What buyers say about Kathana Language Data. Reviews cover the provider, not only this listing.

4.6
4.6

from 2 reviews

Data quality
5.0
Volume and coverage
4.5
Value for money
4.0
Customer service
5.0
  • 4.5 Verified purchaseDemo listing11 Nov 2026

    RLHF pilot turned into a long-term contract

    The 2,000-item preference pilot came back on time with agreement metrics and annotator notes in Hindi and English. Guideline changes were absorbed within a day. We have since scaled to several thousand comparisons a week.

    Data quality
    5/5
    Volume and coverage
    4/5
    Value for money
    4/5
    Customer service
    5/5

    Meera J., Applied scientist, Enterprise AI lab

  • 4.8 Verified purchaseDemo listing11 Nov 2026

    Speaker consent documentation passed our legal review

    Every hour of audio links to a consent record that covers commercial model training, and the speaker metadata let us balance dialects properly. Transcription quality in Tamil and Bengali was the best we have bought.

    Data quality
    5/5
    Volume and coverage
    5/5
    Value for money
    4/5
    Customer service
    5/5

    Vikram R., Speech ML lead, Voice assistant company

Questions buyers ask