Milvus vs pgvector Cost in 2026

Verified as of 2026-05-25 against the official vendor pricing and documentation pages cited below.

Order the three by scale: pgvector wins at small RAG scale if Postgres is already in the stack, the Zilliz Cloud free tier (5 GB plus 100 CU-hours) covers prototyping if it is not, and self-hosting Milvus only pays off at roughly 100M-plus vectors. The headline figure most founders chase, raw managed cost, barely separates the options at small volume; the real lever is whether you already operate Postgres and how many vectors you actually have. This article prices each option on a concrete scenario with the verified rates.

1. Three deployment options, three cost shapes

• pgvector on Postgres. The pgvector extension adds vector search to a database you may already run. Cost is the Postgres tier plus storage; marginal cost of vectors is near zero if Postgres is already there.
• Zilliz Cloud (managed Milvus). Fully managed Milvus with a free tier and usage-based paid plans. Zero operational burden, priced on compute units and storage.
• Self-hosted Milvus. The open-source engine on your own infrastructure. Free software, but you pay for and operate the servers, with a minimum 8 GB RAM standalone footprint^[3].

The cost shapes differ: pgvector is a flat database bill, Zilliz is metered compute plus storage, and self-host is infrastructure plus your operational time. The cheapest depends entirely on scale and on whether Postgres is already running.

2. pgvector total cost, computed

Scenario: 200,000 vectors at 1,536 dimensions, 2,400 queries per day, 1,500 ingests per day. The Embeddings DB Cost engine prices the managed-Postgres pgvector baseline.

The engine reports the Postgres-plus-pgvector line at $35 per month, derived from a managed-Postgres baseline that includes 25 GB of storage. The 1.43 GB storage footprint sits well inside that, so there is no overage. On Supabase, the equivalent host is the Pro tier at $25 per month, which includes 8 GB of disk and $10 in compute credits, with storage overage at $0.125 per GB beyond the included amount^[4]. Either way, if you already run Postgres for application data, the marginal cost of adding pgvector is effectively zero up to the storage cap.

3. Zilliz Cloud managed Milvus cost

Zilliz Cloud's free tier is 5 GB of storage plus 100 CU-hours of compute, which lasts months for a prototype under roughly 500k vectors^[1]. The worked scenario (200k vectors, 1.43 GB) fits inside the free tier on storage, so a prototype runs at zero cost until the 100 CU-hours of compute are consumed.

For paid usage, storage is standardized at $0.04 per GB per month from January 1, 2026 across AWS, Azure, and Google Cloud^[2]. The exact dedicated CU-hour rate is not published as a single flat figure on the official pricing page as of May 2026; Zilliz directs users to its pricing page and calculator for a cluster-specific rate. So the storage component is verifiable ($0.04 per GB-month) while the compute component requires the calculator for your specific cluster.

4. Self-host Milvus: free software, real infrastructure

Milvus is free open-source software, but self-hosting carries infrastructure and operational cost. A standalone Milvus node needs at least 8 GB of RAM^[3], and a production cluster runs many components. At small scale, a single VM with 8 GB RAM might cost $30 to $50 per month, comparable to the managed alternatives but with you carrying the operations.

Self-hosting becomes clearly economical only at large scale, around 100M-plus vectors, where it can run several times cheaper than managed Zilliz. Below that, the operational burden (deploying, monitoring, upgrading a distributed system) outweighs the saving. For a solo founder, self-hosting Milvus is rarely the right first move; it is a scale optimization, not a starting point. The build vs buy framework covers this operational-cost trade-off.

5. The verified comparison table

Dimension	pgvector	Zilliz Cloud	Self-host Milvus
Model cost	$25-$35/mo host (engine baseline)[4]	Free tier, then metered[1]	Infrastructure only (OSS free)[3]
Free tier	Supabase free 500 MB[4]	5 GB + 100 CU-hours[1]	Unlimited (you host it)
Storage rate	$0.125/GB overage (Supabase)[4]	$0.04/GB-mo from Jan 2026[2]	Your disk cost
Compute rate	Included in tier[4]	CU-hour (calculator)[1]	Min 8 GB RAM node[3]
Operational burden	Low (managed)	None (managed)	High (you operate)
Best at scale	Small, Postgres already there	Small-to-mid, no Postgres	100M-plus vectors

6. Which to pick

1. Pick pgvector if you already run Postgres. Marginal vector cost is near zero, and you get SQL filtering plus transactional consistency for free.
2. Pick Zilliz Cloud if you do not run Postgres and want zero operations. The free tier (5 GB plus 100 CU-hours) covers prototyping; paid storage is $0.04 per GB-month from January 2026.
3. Self-host Milvus only if you are at 100M-plus vectors and have the Kubernetes capacity to operate it. Below that scale, the saving does not cover the operational cost.

For the wider picture, the cheapest vector database ranking prices eight vendors at one scenario, and the pgvector vs Pinecone at 200k article goes deeper on the pgvector self-host decision.

Frequently asked questions

Is Milvus or pgvector cheaper for a small RAG app?

At solo-founder scale, pgvector on managed Postgres usually wins on total cost if you already run Postgres for application data, where the marginal cost of adding vectors is near zero. Zilliz Cloud (managed Milvus) has a free tier of 5 GB storage plus 100 CU-hours that covers prototyping, then a serverless or dedicated paid tier. Self-hosting Milvus is free software but needs at least 8 GB RAM and grows to $300 to $600 per month only at 100M-plus vectors, far above small-app scale.

What does Zilliz Cloud cost in 2026?

Zilliz Cloud has a free tier of 5 GB storage plus 100 CU-hours of compute, which lasts months for a prototype under 500k vectors. From January 1, 2026 storage is standardized at $0.04 per GB per month across AWS, Azure, and Google Cloud. The exact dedicated CU-hour rate is not published as a single flat figure on the official pricing page as of May 2026; Zilliz directs users to its pricing page and calculator for cluster-specific rates.

Is self-hosting Milvus worth it?

Only at scale. Milvus is free open-source software, but a standalone deployment needs at least 8 GB RAM, and a production cluster runs many components. Self-hosting becomes economical against managed Zilliz at roughly 100M-plus vectors, where it can be several times cheaper, but at solo-founder scale the operational burden outweighs the saving and pgvector or the Zilliz free tier is simpler.