Google Cloud Pub/Sub Pricing: A Comprehensive Guide

Google Cloud Pub/Sub offers two distinct service models with different pricing structures: Pub/Sub service and Pub/Sub Lite service. This article will explore the pricing components, cost optimization strategies, and help you make informed decisions about your messaging infrastructure costs.

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Important Note: Pub/Sub Lite is being deprecated effective March 18, 2026. Current customers can continue using it until then, but new customers after September 24, 2024, will not have access to Pub/Sub Lite.

Pub/Sub Service Pricing Components

1. Throughput Costs

The fundamental pricing model for Pub/Sub throughput follows a tiered structure:

Base Throughput Pricing

• Free tier: First 10 GiB of throughput per month
• Standard rate: $40 per TiB for all subsequent throughput
• Billing is based on the actual message volume processed

Specialized Subscription Pricing

2. Storage Pricing

Storage costs are fixed at $0.27 per GiB-month and apply to several scenarios:

Topic Storage

• Messages retained in topics with retention policies
• Complete message history preservation

Subscription Storage

• Acknowledged messages with retention enabled
• Unacknowledged messages beyond 24-hour retention
• Snapshot storage for point-in-time recovery

Special Storage Considerations

• The first 24 hours of message storage are free
• Storage billing is calculated daily
• Prorated charges for partial month usage

Storage Pricing Example

Scenario:

• Topic size: 100 GB
• Retention period: 30 days
• Storage rate: $0.27 per GB-month

Monthly storage cost calculation:

100 GB × $0.27 = $27.00 per month

3. Data Transfer Costs

Data transfer pricing follows a hierarchical structure based on network boundaries:

Inbound Data Transfer

• All inbound data transfer to Pub/Sub is free
• No charges for data ingestion from any source

Internal Data Transfer

• Free within the same region
• Standard cloud egress rates apply between regions
• Zone data transfer fees do not apply to Pub/Sub usage

Outbound Data Transfer

• Standard Google Cloud egress rates apply
• Varies based on destination and volume
• Special rates for Cloud Interconnect customers

Message Volume Calculation and Billing

The billable size of a message includes:

Base Components

• Encoded message body string
• Message attributes and key sizes
• 20 bytes for timestamp
• Message ID string size
• Optional fields for early access features

Minimum Billing Unit

• 1 KB minimum charge per request
• Batch processing recommended for messages under 1 KB
• Optimization opportunity for small messages

Example:

Individual processing:

10 messages × 0.2 KB each = 10 KB billable (1 KB minimum each)

Batch processing:

10 messages × 0.2 KB each = 2 KB billable (single request)

Savings: 8 KB per 10 messages

‍Pub/Sub Cost Optimization Strategies

1. Message Batching

Implement effective batching strategies:

• Group small messages into larger batches
• Optimize for the 1 KB minimum billing threshold
• Balance latency requirements with cost-efficiency

2. Storage Optimization

Manage storage costs through:

• Appropriate retention period settings
• Regular cleanup of unnecessary messages
• Use of time-based expiration policies

3. Subscription Management

Optimize subscription costs by:

• Removing unused subscriptions
• Implementing efficient acknowledgment patterns
• Using appropriate subscription types for workloads

Pub/Sub Pricing Considerations

Regional Pricing Variations

While base rates are consistent, consider:

Data Transfer Costs:

• Inter-region transfer rates
• Cross-continental transfer pricing
• Special zones and regions considerations

Service Level Requirements:

• High availability configurations
• Disaster recovery setups
• Multi-region deployments

Enterprise Features and Pricing

Enterprise-grade features that affect pricing:

Security Features:

• Encryption at rest
• Customer-managed encryption keys
• Identity and access management

Reliability Features:

• Exactly-once delivery
• Message ordering
• Replay capability

Pub/Sub Lite Legacy Pricing (Pre-Deprecation)

While being deprecated, understanding Pub/Sub Lite pricing remains relevant for existing implementations until March 2026:

Capacity-Based Pricing Model

How to Manage Pub/Sub Cost?

1. Monitoring and Alerting

Implement comprehensive monitoring:

• Set up billing alerts
• Monitor usage patterns
• Track costs by component

2. Capacity Planning

Effective capacity planning strategies:

• Regular usage analysis
• Growth projections
• Seasonal variation consideration

3. Architecture Optimization

Design considerations for cost efficiency:

• Message size optimization
• Batch processing implementation
• Efficient subscription patterns

How can Airbyte Help Optimize Google Pub/Sub Costs?

1. Efficient Data Integration Across Sources

• Selective Data Syncing: With Airbyte, you can implement incremental syncs instead of full-refresh syncs. By only moving new or changed data from Pub/Sub topics to your destination, you minimize data transfer and storage costs.
• Customizable Filters: Airbyte supports filtering options to sync only the required Pub/Sub messages, reducing unnecessary processing and saving costs on bandwidth and compute.

2. Cost-Efficient Storage Management

• Data Normalization: Normalize Pub/Sub JSON messages into structured formats before storing them in databases like BigQuery. Structured storage is typically more cost-efficient and easier to query, reducing downstream compute costs.
• Compression and Deduplication: Airbyte enables deduplication of data, especially useful for Pub/Sub streams prone to duplication in high-throughput scenarios. This ensures storage and compute are not wasted on redundant data.

3. Optimized Topic and Subscription Management

• Batch Processing: Airbyte can process messages in batches, reducing the number of pull requests made to Pub/Sub subscriptions. This limits operation costs associated with per-request pricing models.
• Rate-Limiting: Configure Airbyte to control the rate at which messages are processed. This ensures you do not overconsume resources during high traffic periods.

4. Seamless Integration With Cost-Effective Destinations

Use Airbyte to route Pub/Sub data to cost-efficient storage solutions such as Google Cloud Storage (GCS) or OLAP systems like DuckDB. This eliminates the need to retain data in Pub/Sub longer than necessary, which can drive up costs.

5. Support for Change Data Capture (CDC)

Leverage Airbyte’s CDC capabilities to sync only changes in real-time instead of the entire dataset. This is particularly valuable when integrating data-intensive applications, as it avoids processing costs tied to large-scale syncs.

6. Granular Monitoring and Alerts

Airbyte provides detailed logs and metrics for every sync operation. You can use this data to analyze the costs of specific Pub/Sub integrations, identify bottlenecks, and optimize configurations accordingly.

7. Scaling with Automation

• Scheduled Syncs: Automate message syncing based on predictable usage patterns. For instance, schedule high-volume syncs during off-peak hours to take advantage of lower resource demand and potentially lower pricing tiers.
• Dynamic Scaling: Configure Airbyte to scale resources dynamically based on the volume of Pub/Sub messages. This avoids over-provisioning or underutilization of resources.

Conclusion

Understanding Google Cloud Pub/Sub pricing requires careful consideration of multiple components and their interactions. By carefully planning your implementation and following best practices for cost optimization, you can build a cost-effective messaging infrastructure that meets your needs while maintaining budget control.

For optimal cost management:

• Regularly review usage patterns
• Implement appropriate optimization strategies
• Monitor and adjust configurations as needed
• Plan for future growth and changes

As the platform evolves and Pub/Sub Lite phases out, staying informed about pricing changes and new features will help ensure the continued cost-effective operations of your messaging infrastructure.