How much RAM and disk does a website need?
Hosting plans are sold in gigabytes, which is unhelpful when you have no idea how many gigabytes a website uses. The honest answer for most sites is: far fewer than the marketing implies. This guide gives real numbers so you can buy the right size rather than the reassuring one.
Memory is what you are really buying
On a VPS, RAM is the resource that runs out first and the one that decides whether your site stays up under load. It holds the web server, the database, and the code processing each visitor's request. When it runs out, the server starts killing processes and your site returns errors.
Rough figures for a Linux server running a normal web stack:
- 1 GB: a small static or brochure site, a personal blog, a bot, or a development box. Tight for WordPress, but workable with caching.
- 2 GB: a comfortable single WordPress site with caching, or a few very small sites. This suits most small business websites.
- 4 GB: WooCommerce or a busier WordPress site, or several small sites together. Room for the database to keep more in memory.
- 6 to 8 GB: a busy store, several active sites, or an application with background workers.
- 10 GB and up: multiple production sites, heavier applications, or anything holding a large working set in memory.
Disk is smaller than you think
A fresh WordPress install is around 100 MB. The operating system on a VPS takes 2 to 4 GB. What grows after that is your media library, and unless you publish video it grows slowly.
A typical small business site with a few hundred images sits under 5 GB in total. A five-year-old blog with a thousand posts and images sits around 10 GB. A shop with several thousand product photos might reach 20 GB.
Two things quietly eat disk and catch people out: backups stored on the same server as the site, and log files that nobody rotates. Neither is your website. Both fill a disk.
Transfer is the one people misjudge
Data transfer is how much leaves the server in a month. The usual mistake is assuming it is enormous.
The median web page is around 2.5 MB. Ten thousand page views a month is therefore roughly 25 GB, and that is the worst case with nothing cached. In practice returning visitors re-download very little, and a free CDN in front of the site cuts the origin's share further.
Most small business sites use between 5 and 25 GB a month. A plan with 1 TB is not being generous to you, it is being irrelevant, which is fine. Transfer only becomes the deciding factor if you serve video or large downloads.
Signs you bought too small
Undersizing shows up as symptoms rather than a warning message:
- The site slows or errors specifically when traffic rises, then recovers
- The database restarts on its own, or the admin area times out while the front page still loads
- You see out-of-memory errors in the logs, or processes being killed
- Uploading a large file or running an import fails partway through
Signs you bought too big
Oversizing is quieter, and it costs you every month. If your memory usage never rises above a third of the plan, your disk is a tenth full after a year, and you use under one percent of the transfer allowance, you are paying for headroom you will never touch.
There is no prize for a server that is permanently bored.
A simple rule
Buy for what you use now with a little room, not for the traffic you hope to have. Upgrading is usually a few minutes of downtime and takes effect immediately, so the cost of guessing low is small and easily corrected. The cost of guessing high is paid every month, forever.
OzVPS VPS plans start at 2 GB of RAM and scale to 10 GB, and you can move up at any time from the client area. If you are unsure which size fits, ask before you order rather than after.