Synth

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SynthJoin Beta
From your data
to your frontier AI
Synth generates state-of-the-art synthetic datasets from your domain documents.
Unlock new capabilities, or bring frontier performance to smaller, more efficient models.

TRUSTED BY AI TEAMS ACROSS EUROPE

01

One-size-fits-all ai was
not trained on your data

AI performance plateaus when training data doesn't cover your domain deep grammar. Synth generates the data to break through.

image displaying very high accuracy (98%) percent for data generation

The knowledge that matters for you isn't in any training set

Industry standards, operational procedures, tacit organizational knowledge: none of this exists in public crawls. No frontier model was trained on it. And in multilingual, sector-specific contexts, the gap only widens.

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Agentic AI demands domain-accurate reasoning

When models direct their own processes, error tolerance drops to near zero. Industrial use cases demand 0–2% error rates and synthetic data is the most efficient way to make your agents accurately reason in your domain, in your language, against your standards, fully integrated into your workflow.

image displaying very high accuracy (98%) percent for data generation

Sensitive data can't leave your infrastructure

High-risk, high-value AI applications require full auditability and control over training pipelines. You need on-premise capability, data residency, and a pipeline you can prove compliant.

image displaying very high accuracy (98%) percent for data generation

Most data generation pipelines are black boxes

No visibility into what's being generated, which models are running, or whether schemas are matched. You can't trust what you can't observe. You can't audit what you can't trace.

02

From domain documents
to training-ready data

Three steps. Full observability at every stage. Your domain expertise becomes frontier-grade synthetic training data.

PDFXMLRegulatoryKnowledge bases
seed ingestion

Seed Ingestion

Upload your domain documents — complex unstructured (PDFs, Word, XML…) and structured data. Synth parses, removes PII, and enriches context automatically.

Q&AReasoningMemorizationMulti-lingual
synthetic generation image

Synthetic Generation

Bespoke generator models produce structured synthetic data at scale — Q&A pairs, reasoning chains, memorization sets, multilingual data — with schema validation at every step.

DeduplicationQuality scoringTrace filtering
verifation layers image

Verification & Training

Formal checks, reasoning-trace filtering, and LLM-based curation ensure quality. Output drives beyond state-of-the-art training efficiency.

03

SOTA data efficiency,
production-validated

Synth datasets consistently produce state-of-the-art model performance across generalist reasoning and domain benchmarks.

<1B

Industry-specialised models surpassing performance of 20x larger ones

200x

More data efficient training compared to leading training mixes

+25%

Average gain in specialised industry benchmarks

BenchmarkSYNTHQwen3Score per 1T tokensEfficiency
TruthfulQA17.69.7
117.3
0.27
435×
TriviaQA17.613.4
117.3
0.37
315×
MMLU46.652.3
310.7
1.45
214×
GPQA Diamond31.424.4
209.3
0.68
309×
XFinBench59.158.4
394.0
1.62
243×
ESGenius63.257.6
421.3
1.60
263×
MMLU-Pro16.731.9
111.3
0.89
126×
04

A Platform you can
actually trust

Full observability, inspectable outputs, and sovereign deployment. No black boxes.

Observable Pipeline

See every step in real time. Token generation rates, model health, schema validation, context utilization. Know exactly what's happening.

On-Premise Deployment

Deploy on-premise within your infrastructure. GDPR and EU AI Act compliant. Your data never leaves your control.

Inspectable Quality

Browse generated data directly in the UI. Quality metrics, sample previews, and distribution breakdowns — no code needed.

API Access

Integrate SYNTH into your AI pipeline. Start generating domain-specific synthetic datasets in minutes with pay-as-you-go pricing.

image of the platform for seeding data
05

Data that meets the standards of the most demanding industries

Wherever domain knowledge, data sovereignty, and operational accuracy are the baseline for AI.

AI
Expertise France

Expertise France

705K token corpus generated

Training ultra-efficient agentic models for deployment on edge and at scale

Health
SpineDAO

SpineDAO

80M token memorization pipeline

Medical reasoning and patient support for spine care, grounded in clinical literature and practioners best practices

Transport
RATP

RATP

100M token reasoning pipeline

Complex psychometric reasoning and real-time distress detection for Paris public transport, where a SYNTH-trained sub-1B model outperforms frontier closed models.

06

Backed by research, recognized by institutions

Pleias builds open knowledge infrastructure for frontier AI, with peer-reviewed research and institutional recognition.

i-Lab 2025 Winner
i-Lab 2025 Winner

France's most prestigious Deep Tech competition, recognizing breakthrough AI research.

NVIDIA Partner
NVIDIA Partner

Nvidia and pleias released the the first massive open synthetic dataset for personas in Europe: Nemotron-Personas-France

SPRIN-D Funded
SPRIN-D Funded

Backed by German Federal Agency for Disruptive Innovation

Start building AI that knows your domain

Join the beta to generate domain-specific training data at scale.
Available as API or on-premise deployment.

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