How to read memory prices
Memory is priced in several layers, and they move at different speeds. This page tracks the layers that can be measured cleanly, and this guide explains what each number is and what it isn’t.
From dollars per chip to dollars per gigabyte
DRAM chips are sold by density in gigabits, and a 16Gb chip holds 2GB, so the chip price divided by two is the chip-level cost per gigabyte. This page shows both figures for every DDR5 spot price. A standard 16GB stick uses eight of these chips, so the tiles at the top also show what the chips for one stick cost.
That figure covers the chips alone, not the circuit board, testing, brand and retail margin that go into a finished kit, so it will not match a store price.
DDR5 and DDR5 eTT
eTT stands for effectively tested. It is a value grade of chip, tested to a statistical standard rather than sold as the maker’s standard branded part, and it trades at a discount. The two prices can move at different speeds, so this page tracks them as separate series.
The memory chip price index
The Bank of Japan publishes monthly price indices for MOS memory integrated circuits, the chip category that includes DRAM and flash, set to 100 in 2020. One tracks what Japanese buyers pay for imported chips and the other what Japanese exporters receive. The import index starts in 2000 and the export index in 2010.
This page uses the contract-currency versions, which leave out moves in the yen’s exchange rate. They reflect actual trade rather than spot quotes, so they can lag or differ from the spot market. The Bank does not split memory into DRAM and flash, so read these for the direction and size of moves in memory prices overall, not for what a chip costs. The newest months are preliminary and can be revised, and we pick up revisions automatically.
How the market odds work
A regulated prediction market lists monthly contracts that ask whether the month’s average DDR5 spot price will finish above a set level. Each one trades between 0 and 100 cents, which reads as the odds. Reading across the levels gives the market’s view of that month.
Where the odds cross 50%, this page shows that price as the market’s midpoint. Where every level it can read is above 50%, it shows the highest one rather than guessing beyond it. That happens often, because levels listed months ago can fall behind a rising price. These are traders’ odds, not a forecast from us. Far-off months are often just standing quotes with few contracts held, so we flag those as thin.
How the numbers are produced
- The weekly and monthly spot prices are the values the contracts settled at. A contract’s value is the same whichever level you look at, and we skip any that disagree.
- Odds are the midpoint of the bid and ask, read once a day. Quotes wider than 20 cents are ignored, because they say too little, and odds are smoothed so that a higher level can never show better odds than a lower one.
- Odds at a round-number level are interpolated between the two nearest usable quotes. Nothing is extrapolated past the last one.
- Spot and odds history accumulate forward. The contracts began in August 2026, so these series are short today and lengthen every week. The official indices come with their full history.