How much RAM and CPU does a website need?
A website needs enough RAM for the operating system, the database cache and every uncached request running at the same time. A cached WordPress site starts at 2 vCPU and 4 GB, WooCommerce at 4 vCPU and 8 GB, and Magento or busy multi-app servers at 8 vCPU and 16 GB. Size by concurrency, not daily visits.
For site owners and developers choosing or upgrading a VPS who want to size memory and CPU from their own measurements.
knowledge
- Read time
- 4 min
- Sections
- 5
- Updated
- 14 Nov 2026
- Written by
- WebJi® team
Last editorial update: 14 November 2026. Prices follow the dated sources on this page; checkout confirms current charges.
What uses RAM and CPU on a website server?
RAM is consumed by the operating system, the database's cache and every uncached request being processed at the same moment; CPU is consumed by running that code, mostly PHP, Node.js or database queries. Daily visitor counts matter far less than how many uncached requests overlap.
| Consumer | What it holds | How it scales |
|---|---|---|
| Operating system and web server | Kernel, Nginx or Apache, system services | Roughly fixed, a few hundred MB |
| MySQL or MariaDB buffer pool | Frequently read tables and indexes | Grows with database size; set by innodb_buffer_pool_size |
| PHP-FPM workers | One process per uncached request in progress | Workers × memory per worker |
| Object cache (Redis/Memcached) | Query results reused between requests | Set by its own memory limit |
| Page cache in RAM, file cache | Recently served files | Uses whatever is left; harmless |
On a KVM VPS the RAM is reserved for your virtual machine, unlike shared hosting where accounts draw from one pool. A vCPU is a scheduled share of a physical core, so CPU-heavy work such as uncached checkout or image processing shows up first as queueing.
How do you calculate how much RAM a PHP site needs?
Add the OS overhead, the database buffer pool and any object cache, then add the number of PHP workers you need multiplied by the average memory per worker. Measure the per-worker figure on your own site rather than guessing.
# average resident memory per PHP-FPM worker (Ubuntu 24.04 uses php-fpm8.3)
ps --no-headers -o rss -C php-fpm8.3 | awk '{s+=$1} END {printf "%.0f MB\n", s/NR/1024}'
# current memory and swap
free -h| Line | Memory |
|---|---|
| OS, Nginx, system services | 0.5 GB |
| MariaDB buffer pool | 1.0 GB |
| Redis object cache | 0.25 GB |
| Headroom for spikes | 0.25 GB |
| Left for PHP workers | 2.0 GB |
| At 80 MB per worker | 2,048 ÷ 80 ≈ 25 workers |
Set PHP-FPM's pm.max_children to that result, not higher; a pool that can spawn more workers than RAM allows pushes the server into swap at the busiest moment.
How much RAM do WordPress, WooCommerce, Magento and Node.js need?
As starting points, a cached WordPress blog or brochure site fits 2 vCPU and 4 GB, a WooCommerce store or growing PHP app fits 4 vCPU and 8 GB, and Magento or several busy apps start around 8 vCPU and 16 GB. Concurrency and caching move these up or down.
| Workload | Starting sample | Move up when |
|---|---|---|
| WordPress blog, brochure site, staging | VPS-Start: 2 vCPU, 4 GB, 60 GB NVMe | Many plugins with no page cache, or editors waiting on the admin |
| WooCommerce, growing PHP or Laravel app | VPS-Growth: 4 vCPU, 8 GB, 120 GB NVMe | Uncached checkouts and a large catalogue overlap at sale time |
| Magento, high traffic, several apps | VPS-Pro: 8 vCPU, 16 GB, 240 GB NVMe | Database cache and workers no longer fit together |
| Small Node.js API or bot | VPS-Start | Heap use grows; set --max-old-space-size deliberately |
WebJi® Linux VPS hosting starts from ₹499 a month before 18% GST, and each sample size is quoted in INR on VPS hosting; checkout confirms the final amount. Full pricing tiers are explained in VPS hosting cost in India.
Why do concurrent visitors matter more than total traffic?
A cached page is served from memory or disk in milliseconds and holds no PHP worker, while each uncached request holds a worker and its memory until it finishes. Ten simultaneous checkouts cost more than a thousand cached product views spread over an hour.
- Page cache: serves repeat views without PHP and is the cheapest capacity you can add.
- Object cache: cuts repeated database queries inside uncached requests.
- Uncached by design: cart, checkout, account and admin pages always run PHP.
- PHP memory_limit: raising it per script does not add RAM the server does not have.
How can you tell a VPS needs more RAM or CPU?
Sustained swap use during the day, out-of-memory kills in the kernel log, and response times that climb at peak hours are the clearest signs of too little RAM; a load average consistently above the vCPU count points to CPU. Check them at the hour the site feels slow.
vmstat 5 5 # si/so columns above 0 = active swapping
sudo journalctl -k | grep -i "out of memory" # kernel OOM kills
uptime # load average vs number of vCPUs (nproc)Before buying more RAM, confirm a page cache is working and slow queries are not the cause. If you are still on shared hosting and hitting entry-process or memory faults, the move is covered in migrating from shared hosting to a VPS, and shared vs VPS hosting explains the difference in limits.
When should you choose a cloud server instead of a larger VPS?
Choose a packaged cloud server when you need Windows Server or fixed published tiers with more memory per core, such as 2 vCPU with 8 GB RAM. WebJi® cloud tiers are ₹5,900, ₹7,900 and ₹11,900 a month before 18% GST for 8, 16 and 32 GB RAM.
The cloud tiers and Linux VPS samples are separate products with separate prices on cloud hosting and VPS hosting; do not combine them into one estimate. Unsure which fits? Email support@webji.services with your stack, peak concurrent users and database size; replies come 24/7 in Hindi and English.
Frequently asked questions
Is 1 GB or 2 GB RAM enough for a WordPress VPS?
It can run a small cached blog, but there is little room for MySQL's buffer pool and a handful of PHP workers, so a traffic spike or a backup job can trigger swapping. For a business site or any store, 4 GB is a safer floor.
Should I add swap space on a VPS?
A small swap file of 1–2 GB is a useful safety net that prevents abrupt out-of-memory kills. It is not extra capacity: if swap is in steady use during busy hours, the server needs more RAM or fewer workers.
Does more CPU make a WordPress site faster?
Only when CPU is the bottleneck. Extra vCPUs let more uncached requests run in parallel, but a single slow page still takes as long on one core. Caching and query fixes usually improve speed more than adding cores.
How much RAM does a cPanel VPS need?
cPanel and WHM add their own services, so plan more memory than a bare Linux server. The WebJi® cPanel VPS sample is 4 vCPU and 8 GB RAM with the licence, quoted by account count before 18% GST.
Commands checked on Ubuntu 24.04 LTS · VPS samples as published on the WebJi® VPS page; quotes confirm sizes and price · Reviewed by the WebJi® team, Jaipur.
Ready to get started with WebJi®?
Join 12,000+ businesses across India and overseas. INR pricing, 18% GST shown before payment and 24/7 email support in Hindi and English — average first reply under 60 minutes.