Firestore

Firestore is a managed, serverless document database for building AI, web, and mobile applications. It stores flexible JSON data and supports vector and full-text search, geospatial queries, and ACID transactions on JSON or BSON-compatible documents. Client SDKs for Android, iOS, and web provide real-time updates and automatic syncing for offline access. Firestore can replicate data across multiple regions with strong consistency; multi-region deployments have a stated 99.999% SLA-backed availability. Named integrations include Google AI Studio, remote MCP, LangChain, and LlamaIndex for generative AI application work. Identity controls connect with Cloud IAM, Cloud Identity Platform, and Firebase Authentication. Data is encrypted before being written to disk, and customer-managed keys are available through Cloud KMS. The free quota applies to one database per project and includes 1 GiB of stored data, daily read, write, and delete allowances, and 10 GiB monthly outbound transfer. New customers receive $300 in credits, separate from that quota. Server client libraries bypass Firestore Security Rules, so server access needs IAM controls.

Firestore combines document storage with multiple query types and client support for real-time and offline use. Teams should account for the one-database free quota and configure IAM controls for server access.

Firestore suits developers building AI, web, or mobile applications that need a document database and client SDKs for Android, iOS, or web. It may also fit applications needing multi-region replication, search, or transactional queries.

Overview

Firestore is a managed cloud database for applications that store data as documents, with client support for mobile and web as well as server access. It suits teams that want flexible document queries and synchronized clients without managing database infrastructure. Its broad query options are a strength, but usage-based billing and the need to secure server access deliberately shape the decision.

Key features

Firestore supports vector, full-text and geospatial queries, along with ACID transactions on JSON or BSON-compatible documents. That makes it a more capable fit than a store limited to straightforward document retrieval, particularly for applications combining several query patterns. The trade-off is that usage and data movement affect cost, so query needs should be considered alongside expected workload.

Android, iOS and web client SDKs provide real-time updates and sync data for offline access. This is useful for applications whose users need current data even when connectivity is intermittent. Firestore also names integrations with Google AI Studio, remote MCP, LangChain and LlamaIndex for generative AI development.

Multi-region deployments use automatic replication with strong consistency, and Firestore states a 99.999% SLA-backed high-availability level for those deployments. Identity controls integrate with Cloud IAM, Cloud Identity Platform and Firebase Authentication; data is encrypted before being written to disk, with customer-managed keys supported through Cloud KMS. One important distinction for server developers: server client libraries bypass Firestore Security Rules and rely on Google Application Default Credentials, so IAM must control server access.

Enterprise edition supports a MongoDB wire-compatible API and existing MongoDB application code, drivers and integrations. That can make it a better fit for teams bringing MongoDB application code than a migration requiring a different API.

Pricing

Firestore is freemium, with a free quota and usage-based Standard and Enterprise editions. The free quota costs nothing and is billed No charge within the stated quota. It covers one database per project, 1 GiB stored data, 50,000 document reads per day, 20,000 writes per day, 20,000 deletes per day and 10 GiB outbound data transfer per month. Quotas reset daily around midnight Pacific time. The one-database limit matters: named databases require billing and do not qualify for the free quota.

New customers receive $300 in free credits to spend on Firestore; those credits are separate from the daily free usage. The free quota is a practical starting point for a small project, but its daily operation caps and single-database restriction may not fit a deployment that needs multiple named databases or sustained higher usage.

Standard edition is usage-based, with charges accruing daily for reads, writes, deletes, storage and network use. Document reads cost $0.03 per 100,000 documents, writes $0.09 per 100,000 documents and deletes $0.01 per 100,000 documents. It is the straightforward paid path for workloads that fit standard document billing, but costs vary with use.

Enterprise edition is also usage-based, charging for read, write and real-time update units, with storage and network billed separately. Read units start at $0.05 per 1 million read units in 4 KB tranches, and write units start at $0.26 per 1 million write units in 1 KB tranches. This edition is the relevant choice for MongoDB wire compatibility, but unit-based billing and separate storage and network charges call for careful workload budgeting.

Platforms

Firestore supports Android, iOS, web and API access. It is a cloud deployment with managed hosting, rather than a self-hosted database option.

Who it's for

Firestore is a strong fit for mobile and web teams that need document storage, live client updates, offline syncing and multiple query types in a managed cloud service. It also suits teams building generative AI applications around its named integrations, or MongoDB application teams that need the Enterprise edition's compatible API. It is less compelling for projects needing several free databases, and server-based applications must be prepared to manage access through IAM rather than Security Rules.

Pros and cons

• Pro: Vector, full-text and geospatial queries plus ACID transactions support varied document workloads.
• Pro: Mobile and web SDKs combine real-time updates with offline syncing, useful for clients that cannot assume continuous connectivity.
• Pro: Multi-region replication, strong consistency and stated 99.999% SLA-backed availability give deployments a clear availability offering.
• Con: The free quota applies to only one database per project; named databases require billing.
• Con: Usage-based charges span operations, storage and network use, making spend dependent on workload.
• Con: Server libraries bypass Security Rules, placing responsibility for server access on IAM configuration.

Alternatives

JayDB is worth considering for readers who prefer a free monthly plan with 1 GB storage, 100,000 reads per month and 10,000 writes per month, rather than Firestore's daily free operation quotas.

restdb.io may fit a small development team that can work within its free Development plan's 3 users, 2,500 records and 1 API call per second limit.

JasDB is another free database option.

LiteDB is a free alternative, including for commercial use.

Couchbase Lite is a paid alternative with a Couchbase Mobile plan that includes Lite, Sync Gateway licensing, peer-to-peer syncing, SQL++ and search capabilities.

MarkLogic offers a Developer plan for noncommercial use with up to 1TB of data, as well as an Enterprise plan.

Oracle Autonomous AI Lakehouse offers an Always Free plan for an unlimited time, subject to capacity limits.

RavenDB is another freemium database option.

For more options, browse Document Databases, Mobile Databases or Database Software.

Verdict

Choose Firestore if your mobile or web application benefits from flexible document queries, real-time updates and offline syncing in a managed cloud service. Its breadth and client support are compelling, but the single-database free quota and workload-dependent charges deserve attention, and server access requires sound IAM controls. Look elsewhere if those constraints outweigh the appeal of its query range and client syncing.