MOSTLY AI vs Tonic.ai

Verdict

Both generate realistic, non-sensitive data so teams can develop and test without exposing production records, but they are shaped differently as products. MOSTLY AI is a single generative-model engine focused on tabular and relational data, with built-in differential privacy controls and an open-source Python SDK for the core engine. Tonic.ai is a family of purpose-built products — Structural for databases, Textual for unstructured text and documents, Fabricate for fully synthetic mock data — that a team picks from depending on what needs protecting.

The clearest differentiator is scope: if the problem is only "make our production database safe to copy into staging," either works. If the problem also includes scrubbing PII out of support tickets, contracts or other unstructured text before it reaches an LLM pipeline, only Tonic.ai's Textual product covers that case among the two.

Choose MOSTLY AI if

• Your data is tabular or relational and a formal differential-privacy guarantee matters to your compliance sign-off.
• You want the option to run the open-source SDK for the core engine rather than only a managed platform.
• You need mock data for staging or simulated edge-case data for stress-testing, alongside standard synthetic generation.

Choose Tonic.ai if

• You need to protect unstructured text or documents feeding an LLM pipeline, not just database rows.
• You want a free tier to start (Fabricate) before committing to a quoted enterprise deployment.
• You want one vendor covering database synthesis, text redaction and from-scratch mock data generation.

The honest caveat

Neither company publishes full pricing for its core database-synthesis product — MOSTLY AI's platform and Tonic Structural are both quote-based, so a real cost comparison requires talking to sales for your actual data volume. Tonic.ai's published figures apply to Fabricate, its smaller mock-data product, not to Structural or Textual.