TOOL-23 · Storage

Storage capacity growth forecaster

Enter what you're using now and how fast it's growing — see how many months until you hit a full threshold, and a month-by-month table to back it up.

Months until threshold

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Month-by-month projection

MonthUsed (TB)% full

Projection assumes linear growth at the rate entered — real usage rarely grows in a perfectly straight line, so revisit this with updated numbers periodically rather than treating one projection as fixed.

Why a flat growth-rate projection is still useful despite being imperfect

Real storage growth is rarely linear — it comes in bursts (a new project, a retention policy change, a one-time data import) rather than a steady monthly trickle. A linear projection isn't meant to predict the exact day capacity runs out; it's meant to convert "we're growing" into a number you can act on, giving you lead time to plan a purchase or a cleanup before the threshold actually arrives.

Picking a threshold below 100%

Planning to an 80% (or similar) threshold rather than 100% leaves headroom for the unexpected — an unplanned large file, a failed cleanup job, or simply the lead time your organization actually needs to approve and receive new storage. Waiting until you're nearly full to start that process is how "we need more storage" turns into an emergency.

How do I find my actual monthly growth rate?

Compare used capacity at two points in time (e.g. the start of this month vs. three months ago) and divide the difference by the number of months — that gives a real average rather than a guess. Most storage systems and NAS dashboards show historical usage if you don't already have a number.

What if growth isn't steady month to month?

Use an average over a longer window (6–12 months) rather than the most recent single month, which can be skewed by a one-time event. This tool's linear model is a planning estimate, not a guarantee — treat the months-remaining figure as "time to start acting," not a hard deadline.

Should the threshold be different for different types of storage?

Often yes — a database volume with performance-sensitive free-space requirements might use 70–75%, while a bulk archive volume with no performance concerns might safely run to 90%+. Set the threshold to whatever number reflects when *your* specific workload actually starts to suffer, not a universal default.

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