# Google Cloud Pub/Sub vs Temporal

Canonical: https://inetgeek.com/compare/google-pubsub-vs-temporal/

Every value below is read from Google Cloud Pub/Sub's and Temporal's own documentation. See https://inetgeek.com/methodology/ for how.

## At a glance

| Criterion | Google Cloud Pub/Sub | Temporal |
| --- | --- | --- |
| Free tier | Yes | Yes |
| Pricing model | Three meters: throughput at $40 per TiB counting both publish and subscribe, storage at $0.27 per GiB-month for anything retained beyond a day, and data transfer when throughput crosses a zone or region boundary. Pub/Sub Lite is a separate product priced on reserved capacity rather than usage. | Per Action, with storage billed separately and split between open and closed workflows. Plans buy SLA tier and support response rather than volume — Essentials is 99.9% with one business day P0 response, Business adds scale. An open-source self-hosted edition runs the same service on your own infrastructure. |
| Included per month | 10 GiB of throughput free per billing account per calendar month, then $40 per TiB. Throughput counts bytes written to a topic plus bytes read from a subscription, so a message published once and read once is billed twice. BigQuery and Cloud Storage subscriptions are $50 per TiB and the 10 GiB does not apply to them; import topics run $50 or $80 per TiB by source. | 1,000,000 Actions a month on Essentials and 2.5 million on Business. An Action is Temporal's own unit — a workflow operation — and is not comparable to a message, an operation or an execution elsewhere in this category. |
| Maximum message size | Pub/Sub bills on bytes rather than message count; the pricing page states no per-message size ceiling and prices throughput and storage instead. | 2 MB maximum payload per request (each Workflow/Activity argument or return value); 4 MB per Event History transaction, non-configurable. |
| Message retention | Retention is configurable and charged rather than granted: $0.27 per GiB-month for messages a topic is configured to retain, for snapshots, and for a subscription's backlog older than one day. A subscription's default retention is 7 days. | Storage rather than a time window: 1 GB of active storage for open workflows and 40 GB retained for closed ones on Essentials, 2.5 GB active on Business. Temporal keeps workflow event history, so retention is bounded by bytes rather than by days — recorded without a magnitude because it is not the quantity this criterion ranks. |
| SOC 2 | Covered under Google Cloud's core SOC 2 Type II reports, issued quarterly for Google Cloud and Google Workspace products generally. | SOC 2 Type II certified; trust center lists SOC 2 Type 2, GDPR, HIPAA and CCPA badges. |
| HIPAA | Pub/Sub is listed as a Covered Product under Google Cloud's HIPAA Business Associate Agreement. | Temporal Cloud is stated to be compliant with HIPAA regulations; HIPAA listed among trust-center certifications. |

## Where they differ

### Pricing model

- Google Cloud Pub/Sub: Three meters: throughput at $40 per TiB counting both publish and subscribe, storage at $0.27 per GiB-month for anything retained beyond a day, and data transfer when throughput crosses a zone or region boundary. Pub/Sub Lite is a separate product priced on reserved capacity rather than usage. ([source](https://cloud.google.com/pubsub/pricing))
- Temporal: Per Action, with storage billed separately and split between open and closed workflows. Plans buy SLA tier and support response rather than volume — Essentials is 99.9% with one business day P0 response, Business adds scale. An open-source self-hosted edition runs the same service on your own infrastructure. ([source](https://temporal.io/pricing))

### Included per month

- Google Cloud Pub/Sub: 10 GiB of throughput free per billing account per calendar month, then $40 per TiB. Throughput counts bytes written to a topic plus bytes read from a subscription, so a message published once and read once is billed twice. BigQuery and Cloud Storage subscriptions are $50 per TiB and the 10 GiB does not apply to them; import topics run $50 or $80 per TiB by source. ([source](https://cloud.google.com/pubsub/pricing))
- Temporal: 1,000,000 Actions a month on Essentials and 2.5 million on Business. An Action is Temporal's own unit — a workflow operation — and is not comparable to a message, an operation or an execution elsewhere in this category. ([source](https://temporal.io/pricing))

### Maximum message size

- Google Cloud Pub/Sub: Pub/Sub bills on bytes rather than message count; the pricing page states no per-message size ceiling and prices throughput and storage instead. ([source](https://cloud.google.com/pubsub/pricing))
- Temporal: 2 MB maximum payload per request (each Workflow/Activity argument or return value); 4 MB per Event History transaction, non-configurable. ([source](https://docs.temporal.io/cloud/limits))

### Message retention

- Google Cloud Pub/Sub: Retention is configurable and charged rather than granted: $0.27 per GiB-month for messages a topic is configured to retain, for snapshots, and for a subscription's backlog older than one day. A subscription's default retention is 7 days. ([source](https://cloud.google.com/pubsub/pricing))
- Temporal: Storage rather than a time window: 1 GB of active storage for open workflows and 40 GB retained for closed ones on Essentials, 2.5 GB active on Business. Temporal keeps workflow event history, so retention is bounded by bytes rather than by days — recorded without a magnitude because it is not the quantity this criterion ranks. ([source](https://temporal.io/pricing))

### SOC 2

- Google Cloud Pub/Sub: Covered under Google Cloud's core SOC 2 Type II reports, issued quarterly for Google Cloud and Google Workspace products generally. ([source](https://cloud.google.com/security/compliance/soc-2))
- Temporal: SOC 2 Type II certified; trust center lists SOC 2 Type 2, GDPR, HIPAA and CCPA badges. ([source](https://temporal.io/security))

### HIPAA

- Google Cloud Pub/Sub: Pub/Sub is listed as a Covered Product under Google Cloud's HIPAA Business Associate Agreement. ([source](https://cloud.google.com/security/compliance/hipaa))
- Temporal: Temporal Cloud is stated to be compliant with HIPAA regulations; HIPAA listed among trust-center certifications. ([source](https://temporal.io/security))

## Which should you choose?

Pick Google Cloud Pub/Sub if Google Cloud systems that want messaging without capacity planning — throughput is metered rather than provisioned, and 10 GiB a month costs nothing.

Pick Temporal if Long-running, stateful workflows where losing execution history is the failure that matters — Temporal keeps event history as first-class storage rather than logs that expire.

Consider something else: Google Cloud Pub/Sub — Throughput counts bytes both in and out, so a message read once is billed twice, and retention is a storage charge rather than an included window — the headline $40 per TiB is not the whole bill.

Consider something else: Temporal — Entry is $100 a month before any usage, and the unit is an Action, which does not map onto messages or task runs — budgeting requires modelling your workflows, not counting jobs.

## Documented by only one

- Entry paid plan: Temporal: $100/month for Essentials, including 1 million Actions, 1 GB active storage and 40 GB retained storage. Business starts at $500/month with 2.5 million Actions.
- Startup credit program: Temporal: Temporal Cloud startup credits: $6,000, for funded startups that have raised $30M or less.
- Regions: Temporal: 20 regions for Temporal Cloud Namespaces: 14 AWS regions and 6 Google Cloud regions, each with a PrivateLink or Private Service Connect endpoint.
- Ingest price per GB: Google Cloud Pub/Sub: $40 per TiB, which is $0.039 per GiB, for standard publish and subscribe throughput in every Google Cloud region.
- Maximum delay: Temporal: Timers (durable sleeps) may run up to 100 years in Temporal Cloud.
- Concurrency: Temporal: 500 Actions per second per Namespace by default, auto-scaling above that with On-Demand Capacity; 20,000 Activity and 20,000 Workflow Task pollers per Namespace.
- ISO 27001: Google Cloud Pub/Sub: The Google Cloud Services ISMS holds an accredited ISO/IEC 27001 certification, audited by an independent third party.
- GDPR / data residency: Temporal: GDPR compliant with a DPA reflecting GDPR; Namespaces do not share data processing or storage across regional boundaries.
- PCI DSS: Google Cloud Pub/Sub: Pub/Sub is listed among the individual Google Cloud products certified against PCI DSS via annual third-party audit.
- Encryption at rest: Temporal: Persistence layer and Elasticsearch index encrypted at rest with AES-256-GCM; TLS 1.3 in transit.
- Customer-managed keys: Temporal: Client-side Data Converter encrypts payloads with your keys on your Workers before they reach Temporal Cloud, which cannot decrypt them; no server-side KMS option stated.
- Role-based access control: Temporal: Account-level roles (administrator, developer, read-only) plus Namespace-level permissions; custom roles, SAML and SCIM documented.
- Private networking / VPC: Temporal: AWS PrivateLink or GCP Private Service Connect to Namespaces, alongside the default public endpoints.

## Questions this comparison answers

**Should I choose Google Cloud Pub/Sub or Temporal?**

Pick Google Cloud Pub/Sub if Google Cloud systems that want messaging without capacity planning — throughput is metered rather than provisioned, and 10 GiB a month costs nothing.
Pick Temporal if Long-running, stateful workflows where losing execution history is the failure that matters — Temporal keeps event history as first-class storage rather than logs that expire.