Multimodal AI training data.
In any language, across every modality.

Verified contributors across
text, audio, and visual tasks

Years running data programs at production scale for frontier labs

What’s standard here
isn’t standard elsewhere.

These aren’t premium add-ons. They’re how every program runs.

  • Multilingual coverage that goes the full depth
  • 155+ locales across every modality. Audio in the target dialect. Images annotated with cultural context for the target market. Documents processed by script-literate contributors.
  • Domain-credentialed contributors where it matters
  • Medical, legal, financial, and technical content goes to contributors with validated domain credentials in the relevant field and language. Not generalist workers attempting specialist work.
  • Cross-modal consistency, enforced
  • Same ontology and annotation guidelines across all data types in a program. Inconsistency between modalities is one of the main failure modes in multi-vendor programs. It doesn’t happen here because there’s one team and one standard.
  • Original data collection, fully managed
  • Contributor sourcing, consent, rights clearance, structured delivery. For programs requiring data generated from scratch rather than existing assets annotated.
  • QA with teeth
  • Inter-annotator agreement scoring, gold task calibration, audit trails. Accuracy thresholds are set before work begins, not negotiated after delivery.
  • Compliant by design
  • All original collection includes explicit contributor consent and appropriate licensing. Programs scoped to GDPR, HIPAA, and equivalent frameworks — documented, not assumed.
  • Delivery formats that don’t require cleanup
  • JSON, CSV, COCO, PASCAL VOC, custom schemas. Format agreed at scoping. Data arrives structured and ready.
  • Same infrastructure at any scale
  • Pilot to production, the same quality controls and team structure apply regardless of volume.

Language is the hard part. We solved it first.

The providers who built for English and added language coverage later show the seams at scale. Welo Data built the other way around — and it changes what’s possible across every modality.

155+ locales means 155+ locales

Not 155+ with English, Spanish, and Mandarin well-covered and everything else best-effort. The same contributor network depth, dialect coverage, and quality infrastructure applies across the full locale set — including the languages where most providers quietly under-deliver.

One team across all modalities

Image, video, audio, text, document. One delivery team, one set of quality standards, one point of accountability. The cross-modal consistency problems that come from multi-vendor structures don’t arise here because there isn’t one.

Cross-modal QA before it reaches you

Paired data — image-text, audio-visual, video-caption — is checked for semantic consistency before delivery. The error surfaces at our QA stage, not yours.

Specialist content handled by specialists

Medical imaging annotated by contributors with validated medical credentials. Legal documents reviewed by contributors with legal domain knowledge, in the target language. Not a common capability.

The infrastructure to run it at scale

Welo Data’s contributor network and program infrastructure have operated at production scale across languages and data types for over 20 years. That matters when a program has to run without the wheels coming off.

The clients who needed to know it works

The world’s leading frontier labs and Mag-7 technology companies use Welo Data for programs where data quality and linguistic precision are non-negotiable.

Questions worth asking. Straight answers.

Single delivery team, single ontology. The same annotation guidelines and quality standards are applied across all modalities in a program — not managed separately by modality. Locale-specific guidelines are nested within the master ontology, not run in parallel. When a program combines image, audio, and text across multiple languages, there’s one QA framework that covers all of it.

Work stops on the affected task type. Contributors are recalibrated against gold tasks before resuming. If the issue is systemic — a guideline gap, an ambiguous edge case — the ontology is updated and the affected batch is re-reviewed. Accuracy thresholds are agreed before work begins. Mid-program renegotiation isn’t how this works.

Audio is collected and annotated by native speakers of the target language and dialect — not transcribed in English and translated. Images and video are annotated by contributors with the cultural and linguistic context to label them accurately for the target market. The 155+ locale figure applies across all modalities.

Welo Data handles contributor sourcing, consent, rights clearance, and structured delivery. Compliance requirements — GDPR, HIPAA, and equivalent — are scoped into program design from the start and documented throughout. Not handled on request after the fact.

For programs pairing modalities — image-text, audio-visual, video-caption — semantic consistency across the pair is a discrete QA step before delivery. Individual label accuracy is necessary but not sufficient; the relationship between paired elements is reviewed separately. Mismatches are corrected and re-reviewed before the dataset leaves the pipeline.


Yes. Secure lab setup, safety compliance, roster management, multilingual motion and voice collection, annotation, and structured delivery. See how Welo Data runs physical AI programs →


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