Union.ai vs VAST Data
Which Data Engineering AI tool is better in 2026?
Union.ai
AI development infrastructure for durable, production-grade ML and agent workflows
VAST Data
Unifying software layer for AI infrastructure
Side-by-side
VAST Data is the more established option (raised $2.4B); pricing is comparable on both sides.
| Metric | Union.ai | VAST Data |
|---|---|---|
| Taglinei | AI development infrastructure for durable, production-grade ML and agent workflows | Unifying software layer for AI infrastructure |
| Foundedi | 2021 | 2016🏆 |
| HQi | Bellevue, US | US |
| Employeesi | 51-200🏆 | 201-500 |
| Neuron scorei | 70 | 90🏆 |
| Total fundingi | $58M | $2.4B🏆 |
| Latest roundi | Series A · Feb 2026 | Series F · Apr 2026 |
| Valuationi | — | $30B🏆 |
| Cheapest paid plani | Pricing not disclosed | — |
| Free plani | ✗ | ✗ |
| Free triali | ✓ | ✗ |
| Top tier pricei | Pricing not disclosed | Enterprise · Contact sales |
| Pricing summaryi | Free trial | 1 published plans |
| Categoriesi |
Capability matrix
Developer-facing capabilities and access signals for Union.ai and VAST Data.
| Capability | Union.ai | VAST Data |
|---|---|---|
| MCP support | ✗ | ✗ |
| Public API | ✓ | ✗ |
| Webhooks | ✗ | ✗ |
| OAuth 2.0 | ✗ | ✗ |
| SDK languages | — | — |
| Free plan | ✗ | ✗ |
| Free trial | ✓ | ✗ |
| Verified | ✗ | ✗ |
| Active deal | ✗ | ✗ |
🟢 Strengths of Union.ai
- Offers a free trial
- Newer company (2021)
🔵 Strengths of VAST Data
- Has raised more capital ($2.4B vs $58M)
- Higher Neuron score (90 vs 70)
- More mature (2016)
Which should you choose?
Choose VAST Data if price matters most — it starts at Enterprise · Contact sales, which is friendlier for teams watching burn. Both AI Data Engineering tools ship core features, so the cost delta often decides it for small teams and solo operators.
Choose VAST Data if you want the most established option — it has raised $2.4B, suggesting more runway for enterprise features, support, and long-term roadmap. For mission-critical workflows or larger teams, that stability often outweighs a lower monthly price.
Frequently asked questions
Union.ai vs VAST Data — which is better?
It depends on your priority. Union.ai is the leaner option; VAST Data has broader feature depth. See the side-by-side table above.
Is Union.ai cheaper than VAST Data?
No — VAST Data's cheapest paid plan is Enterprise · Contact sales, while Union.ai's is Free trial.
Do Union.ai and VAST Data offer free plans?
Union.ai: Free trial only. VAST Data: Paid only.
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