dynamodb calculator

What this DynamoDB calculator helps you estimate

Amazon DynamoDB is fast, scalable, and serverless—but pricing can look confusing the first time you model a workload. This calculator gives you a practical estimate of your monthly spend by combining request capacity costs with storage and backup costs.

Use it for quick architecture decisions, budgeting, or comparing two usage patterns before deploying to production.

How DynamoDB pricing works (simplified)

1) Capacity pricing

Capacity is billed differently depending on your table mode:

• On-demand: You pay per read request and write request consumed.
• Provisioned: You pay for provisioned read capacity units (RCUs) and write capacity units (WCUs) per hour, whether fully used or not.

2) Storage pricing

Your table data is billed per GB-month. As item count and item size grow, storage spend usually becomes a bigger part of your bill.

3) Backup and recovery pricing

If you enable features like point-in-time recovery (PITR) or backups, there is additional storage cost. This page includes a simple field for backup GB-month so you can account for it directly.

On-demand vs provisioned: when each makes sense

On-demand is usually better when:

• Traffic is unpredictable or spiky.
• You want to minimize capacity planning effort.
• You are early-stage and still learning real usage patterns.

Provisioned is usually better when:

• Traffic is steady and predictable.
• You can tune RCUs and WCUs to actual needs.
• You want more control over baseline cost.

How to use this calculator correctly

1. Select your billing mode.
2. Enter realistic monthly traffic or provisioned capacity numbers.
3. Set storage and backup usage in GB-month.
4. Adjust price fields to your AWS region.
5. Click Calculate Monthly Cost and review the breakdown.

If your workload varies by time of day, run multiple scenarios (low, expected, peak) to create a safer budget range.

Quick optimization checklist

• Use the right primary key pattern to avoid hot partitions.
• Store only necessary attributes to reduce item size and storage cost.
• Add TTL for temporary data you do not need forever.
• Review and prune unused GSIs or over-indexed attributes.
• Monitor CloudWatch metrics and resize provisioned capacity regularly.
• Choose table class and backup policy intentionally—not by default.

Important notes

This calculator is intentionally streamlined. Real AWS bills may also include global tables replication, data transfer, DynamoDB Streams, exports, DAX, and other service interactions. Treat this tool as a planning model, then validate with your actual billing and usage metrics.

Still, even a simple calculator like this is enough to prevent common surprises and make better design trade-offs early.