Is DynamoDB free?
Partly. DynamoDB has an always-free tier, not a fully free service. Every AWS account gets 25 GB of storage plus 25 provisioned write and 25 read capacity units — roughly 200 million requests per month — free each month for Standard-class tables. Usage beyond that, and on-demand capacity, is billed per request and per GB.
What the always-free tier includes
- 25 GB of Standard-class table storage.
- 25 provisioned WCUs and 25 provisioned RCUs (enough for about 200 million requests/month).
This is an "always free" offer — it does not expire after the 12-month new-account window.
Where "about 200 million requests" comes from
AWS quotes the allowance as "enough for about 200M requests/month (depending on item size)" and shows neither the arithmetic nor what the parenthesis is hiding. Both are worth having.
A month of provisioned capacity is 730 hours, or 2,628,000 seconds. 25 RCU held for that long is 65.7 million strongly consistent reads of an item up to 4 KB, and an eventually consistent read costs half a unit, so 131.4 million of those instead. 25 WCU is 65.7 million writes of an item up to 1 KB. Add them and you get 197.1 million.
The parenthesis matters more than the headline, because writes round up per 1 KB:
| Average item size | Reads/month | Writes/month | Total |
|---|---|---|---|
| 1 KB | 131,400,000 | 65,700,000 | 197,100,000 |
| 4 KB | 131,400,000 | 16,425,000 | 147,825,000 |
| 400 KB | 1,314,000 | 164,250 | 1,478,250 |
Quadruple your item size and the free tier buys a quarter of the writes, while reads are untouched because 4 KB is where read rounding starts. At the 400 KB maximum the allowance is effectively gone.
What is billed
The free tier is applied each month on a per-Region, per-payer-account basis across your provisioned Standard-class tables. Storage over 25 GB, provisioned capacity above 25/25, on-demand request charges, backups, streams, and global-table replication are all billed.
Note on capacity mode
The free allowance applies to provisioned capacity. On-demand tables are billed per read and write request from the first one.
That distinction is the whole answer for most people, because on-demand is the default most tables end up on. Run the 1 KB workload above on-demand in us-east-1 and the same traffic costs $49.28 a month: 65.7 million read request units at $0.125 per million is $8.21, and 65.7 million write request units at $0.625 per million is $41.06. Identical requests, identical region, nothing free about it.
Go deeper
Estimate your bill with the DynamoDB pricing calculator and compare modes in on-demand vs provisioned. Download DynoTable to browse and query your tables.
References
- Amazon DynamoDB Pricing — AWS
- What is Amazon DynamoDB? — Amazon DynamoDB Developer Guide
- Quotas in Amazon DynamoDB — Amazon DynamoDB Developer Guide
Last verified 2026-07-13 against the official AWS documentation linked above; free-tier terms and us-east-1 unit prices re-checked 2026-07-28.