# Amazon SQS vs Google Cloud Pub/Sub

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

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

## At a glance

| Criterion | Amazon SQS | Google Cloud Pub/Sub |
| --- | --- | --- |
| Free tier | Yes | Yes |
| Pricing model | Per request, not per message: every API action counts, and a 1 MiB payload is billed as 16 requests. FIFO queues cost $0.50 per million against standard's $0.40 in us-east-1, and fair queue requests add $0.10 per million on top of the standard rate. | 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. |
| Included per month | 1,000,000 requests a month free, permanently and across all regions. Beyond that, standard queues are $0.40 per million in us-east-1, falling to $0.30 above 100 billion and $0.24 above 200 billion. | 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. |
| Maximum message size | 256 KB per message. A single request carries 1 to 10 messages up to 1 MiB total, and each 64 KB chunk of payload is billed as one request. | Pub/Sub bills on bytes rather than message count; the pricing page states no per-message size ceiling and prices throughput and storage instead. |

## Where they differ

### Pricing model

- Amazon SQS: Per request, not per message: every API action counts, and a 1 MiB payload is billed as 16 requests. FIFO queues cost $0.50 per million against standard's $0.40 in us-east-1, and fair queue requests add $0.10 per million on top of the standard rate. ([source](https://pricing.us-east-1.amazonaws.com/offers/v1.0/aws/AWSQueueService/current/us-east-1/index.json))
- 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))

### Included per month

- Amazon SQS: 1,000,000 requests a month free, permanently and across all regions. Beyond that, standard queues are $0.40 per million in us-east-1, falling to $0.30 above 100 billion and $0.24 above 200 billion. ([source](https://pricing.us-east-1.amazonaws.com/offers/v1.0/aws/AWSQueueService/current/us-east-1/index.json))
- 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))

### Maximum message size

- Amazon SQS: 256 KB per message. A single request carries 1 to 10 messages up to 1 MiB total, and each 64 KB chunk of payload is billed as one request. ([source](https://aws.amazon.com/sqs/pricing/))
- 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))

## Which should you choose?

Pick Amazon SQS if AWS-resident systems that want a queue with a permanent free million requests a month and no capacity to plan — SQS scales without a throughput setting to 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.

Consider something else: Amazon SQS — Billing is per request rather than per message, and a 1 MiB payload counts as sixteen, so chatty polling or large messages cost far more than the message count suggests.

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.

## Documented by only one

- 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.
- 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.
- Dead letter queue: Amazon SQS: Supported

## Questions this comparison answers

**Should I choose Amazon SQS or Google Cloud Pub/Sub?**

Pick Amazon SQS if AWS-resident systems that want a queue with a permanent free million requests a month and no capacity to plan — SQS scales without a throughput setting to 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.