MongoDB AtlasThe intelligent data platform for the AI era
vs
PostgreSQLThe world's most advanced open source database
Comparison · Vector Databases · weekly run Nov 2
MongoDB Atlas vs PostgreSQL
Which one do AI engines recommend, and how do they differ on price, fit and features?
The short answer
PostgreSQL is the stronger AI pick in Vector Databases: it has a visibility score of 49 versus 12.7 for MongoDB Atlas, and ranks ahead in 87% of the answers that name both.
Choose MongoDB Atlas if…
- You need ISO/IEC 27001:2022 or FedRAMP Moderate (Atlas for Government) or TX-RAMP Level 2 or PCI DSS or HIPAA or GDPR or CSA STAR coverage
- You prefer a larger, established vendor (5,000+ employees)
- stores documents and vector embeddings together in one system
- good fit for teams already using MongoDB
Choose PostgreSQL if…
- You want the brand AI engines rank higher (49 vs 12.7)
- AI answers describe it more positively (35% vs 28% positive)
- Free open-source software
- Adds vector search to an existing PostgreSQL database without a new database
AI visibility side by side
Latest weekly run · Nov 2
| Metric | MongoDB Atlas | PostgreSQL |
|---|---|---|
| Visibility score | 12.7% | 49% |
| Change vs last week | New | New |
| Rank in Vector Databases | #8 | #3 |
| Share of voice | 5.5% | 12.6% |
| Mentions this run | 26 | 59 |
| Positive in AI answers | 28% | 35% |
The stronger value in each row is marked with a ✓.
Visibility score trend
Weekly runs over the last 60 days
MongoDB Atlas 0pp · PostgreSQL 0pp over 0 weekly runs.
Engine by engine
PostgreSQL leads on 3 of 3 engines
ChatGPT
AI Mode
Perplexity
MongoDB AtlasPostgreSQL
Head to head in AI answers
23 engine answers name both brands
3MongoDB Atlas ranked higher
20PostgreSQL ranked higher
| Prompt | Engine | MongoDB Atlas | PostgreSQL |
|---|---|---|---|
| How do I choose a vector database for a mid-market team? | ChatGPT | #6 | #1 |
| How do I choose a vector database for a mid-market team? | AI Mode | #5 | #4 |
| What features matter most in a vector database? | ChatGPT | #6 | #4 |
| How do companies store and search embeddings without a dedicated tool? | ChatGPT | #5 | #1 |
| How do companies store and search embeddings without a dedicated tool? | AI Mode | #7 | #3 |
| What should a vector database integrate with? | ChatGPT | #2 | #1 |
| What should a vector database integrate with? | AI Mode | #2 | #1 |
| What are the best Vector Databases tools in 2026? | ChatGPT | #10 | #5 |
| What are the best Vector Databases tools in 2026? | AI Mode | #8 | #6 |
| Top vector database options for B2B SaaS companies | AI Mode | #5 | #4 |
| Top vector database options for B2B SaaS companies | Perplexity | #8 | #3 |
| Best vector database for enterprise | AI Mode | #7 | #3 |
Features, pricing & fit
| Dimension | MongoDB Atlas | PostgreSQL |
|---|---|---|
| Pricing model | Usage-based | — |
| Entry price | Free; paid from $0.011 / mo | — |
| Free plan | Yes | — |
| Deployment | Fully managed cloud with Atlas Core and Atlas Infinite deployment options, or self-managed through MongoDB Enterprise Advanced | — |
| Integrations | 100+ | — |
| Compliance | ISO/IEC 27001:2022, FedRAMP Moderate (Atlas for Government), TX-RAMP Level 2, PCI DSS, HIPAA, GDPR, CSA STAR | — |
| Support | Basic Support included free with Atlas, Paid plans with faster response times, Named Technical Support Engineers, Extended Lifecycle Support add-on | Community mailing lists, Community events and local user groups |
| Headquarters | New York, NY, United States | United States |
| Employees | 5,000+ | 51–200 |
| Funding | IPO and stock offering · $311M raised | — |
| Best for | Development teams building AI applications and agents that need operational data, vectors and search in one platform | — |
Plans side by side
MongoDB Atlas
Free (M0)$0hour
Flex$0.011hour (up to $30/month)
Dedicated$0.08hour (starts at $56.94/month)
Atlas Infinite (Public Preview)$0.09hour
Enterprise Advanced (Self-managed)Customcontact sales
PostgreSQL
Pricing not available.
Pros and cons
Themes from the AI answers that mention each brand
MongoDB Atlas
- stores documents and vector embeddings together in one system
- good fit for teams already using MongoDB
- built-in vector search without extra infrastructure
- vector search included in Atlas pricing with a free M0 tier
- integration with Databricks Lakebase
PostgreSQL
- Free open-source software
- Adds vector search to an existing PostgreSQL database without a new database
- Wide compatibility with drivers, BI tools, and language ecosystems
- Broad deployment and transparent self-hosted pricing
- Hosting, backups, and maintenance must be paid for when self-hosted
Data collected ·ChatGPT, Perplexity, Google AI Mode·coverage 100%·next run
Cite as: SlateIndex, “MongoDB Atlas vs PostgreSQL”, https://slateindex.ai/compare/mongodb-atlas-vs-postgresql, data of Nov 2, 2026. Licence: CC BY 4.0.