Project Redshift storage after columnar compression and growth, and compare RA3 managed storage against DC2 local capacity.
Redshift stores data column by column and encodes each column separately, so 3x to 4x compression is normal and the raw figure badly overstates what you pay for. On RA3 that compressed volume is billed as managed storage at a flat GB-month rate and the node count is driven purely by query concurrency, whereas on DC2 the local SSD is bundled into the node and capacity alone can force nodes you do not need for compute. The managed-storage rate is an editable input with a realistic us-east-1 default — confirm current Redshift prices with AWS for your region. The RA3 versus DC2 decision is usually settled by this arithmetic: once capacity rather than concurrency dictates the DC2 node count, RA3 with separately billed managed storage is almost always cheaper.
Redshift Storage
compressed = raw ÷ compression ratio; projected = compressed × (1 + annual growth)^years; DC2 nodes = ceil(projected TB ÷ TB per node).
compressed = raw ÷ compression ratio; projected = compressed × (1 + annual growth)^years; DC2 nodes = ceil(projected TB ÷ TB per node). Redshift stores data column by column and encodes each column separately, so 3x to 4x compression is normal and the raw figure badly overstates what you pay for. On RA3 that compressed volume is billed as managed storage at a flat GB-month rate and the node count is driven purely by query concurrency, whereas on DC2 the local SSD is bundled into the node and capacity alone can force nodes you do not need for compute. The managed-storage rate is an editable input with a realistic us-east-1 default — confirm current Redshift prices with AWS for your region.
The RA3 versus DC2 decision is usually settled by this arithmetic: once capacity rather than concurrency dictates the DC2 node count, RA3 with separately billed managed storage is almost always cheaper.
This calculator takes 7 inputs: Raw uncompressed data, Columnar compression ratio, Annual data growth, Plan ahead, Node family, RA3 managed storage price, DC2 storage per node. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.
Run ANALYZE COMPRESSION on a representative table rather than guessing. Wide fact tables with low-cardinality columns often exceed 4x, while pre-compressed or high-entropy data such as hashes and encrypted blobs may barely compress at all.