RAM Test: Memory Speed and Capacity in Your Browser
Measure how fast your memory reads and writes, how quickly random accesses return, and how much memory the browser can use.
Speed details
Your recent runs
- No runs yet
A browser cannot scan physical RAM for errors. For that, use a boot-time tool such as MemTest86 or Windows Memory Diagnostic.
Memory, or RAM, holds everything your computer is working on right now: open apps, browser tabs, game levels and the operating system itself. Two things about it matter for performance. How much you have decides how many things can stay open before the system slows down, and how fast it is decides how quickly the processor can get data. This RAM test measures the speed side in your browser and reports what your device reveals about capacity.
The speed test measures memory bandwidth for writing, reading and copying large blocks of data, plus random access latency, the time it takes to fetch data from an unpredictable place in memory. An optional allocation test shows how much memory the browser can reserve for this tab. Your recent results are saved for comparison.
How to use the RAM test
- Close other heavy tabs and apps so more memory is free.
- Press Test memory speed. The page may pause briefly while large blocks are processed.
- Read your bandwidth and latency, and the details for write, read and copy speed.
- Optionally press Allocation test to see how much memory the browser can reserve, up to 2 GB.
- Compare with your saved runs after changing memory settings or hardware.
What the test measures
Bandwidth
The test writes, reads and copies arrays of 64 MB, far larger than the processor’s caches, so the data has to travel to and from main memory. The best of several repetitions is used, and the result is shown in gigabytes per second. The headline bandwidth is the average of the three.
Latency
Latency is measured with a random pointer chase: a 64 MB table is shuffled into a single random loop, then followed step by step, so every step jumps to a new, unpredictable place. That defeats caching and prefetching, and the average time per step approximates memory latency in nanoseconds.
Reported memory and allocation
Browsers report device memory only as a rounded hint, capped at 8 GB in most browsers for privacy. The allocation test reserves memory in 64 MB blocks until it reaches 2 GB or the browser refuses, then releases everything. The result is the browser’s limit for this tab, not your total RAM.
Understanding your results
| Measurement | Typical browser result |
|---|---|
| Bandwidth, older or single-channel | Under 5 GB/s |
| Bandwidth, typical recent system | 5 to 15 GB/s |
| Bandwidth, fast dual-channel | Over 15 GB/s |
| Random access latency | About 60 to 150 ns |
Browser numbers are lower than the theoretical figures printed on memory modules, because JavaScript adds overhead and the test measures real, practical transfers. Use them to compare runs, not to check a specification.
What a browser cannot test
A web page cannot scan your physical RAM for errors, see individual memory modules or read their rated speed and timings. If you suspect faulty memory, for example random crashes or blue screens, use a boot-time tool such as MemTest86 or Windows Memory Diagnostic, which test every address outside the operating system.
Why reported memory is rounded
Exact memory size helps websites identify devices, so browsers round it to a few standard values. That protects privacy, which is why the test shows it as a minimum rather than an exact amount.
How to improve memory performance
- Enable XMP or EXPO in the BIOS on desktops so memory runs at its rated speed.
- Use two matching sticks in the correct slots for dual-channel mode.
- Close tabs and apps you are not using to free memory.
- Plug laptops into power; power saving can lower memory and processor speed.
- Add more RAM if the system slows down whenever many apps are open.
- Restart occasionally so leaked memory from long-running apps is released.
Signs you need more memory
Memory shortages show up as slowdowns rather than errors. Switching between apps takes a moment longer, browser tabs reload when you return to them, games stutter when loading new areas, and the storage activity light stays busy even when you are not saving anything. On Windows, open Task Manager and look at the Memory graph; if it stays above about 85 percent during normal use, more RAM will help. On a Mac, Activity Monitor shows memory pressure, and a yellow or red graph means the system is struggling.
How much RAM do you need?
For everyday browsing and office work, 8 GB is workable and 16 GB is comfortable. Gaming usually benefits from 16 GB, and 32 GB helps with streaming while gaming, video editing and large projects. Having more than you use does not make a computer faster, but running out slows everything down as the system swaps to storage.
Related tools
The PC benchmark includes memory alongside CPU and graphics. The CPU test shows processor performance, which depends on fast memory, and the system information tool and browser information tool show what your device reports about memory and hardware.
Frequently asked questions
Can a website test my RAM?
It can measure memory speed and how much the browser can use, but it cannot scan physical RAM for errors.
What is memory bandwidth?
How much data can move between memory and processor per second, shown in gigabytes per second.
What is memory latency?
The time to fetch data from a random place in memory, shown in nanoseconds. Lower is better.
Why does it say at least 8 GB when I have 32 GB?
Browsers round and cap reported memory for privacy, often at 8 GB.
What does the allocation test show?
How much memory the browser can reserve for this tab, up to 2 GB. It is not your total RAM.
How do I check RAM for errors?
Use a boot-time tool such as MemTest86 or Windows Memory Diagnostic.
Why is my bandwidth lower than my RAM's rated speed?
Browser tests include JavaScript overhead and measure practical transfers, which are always lower than the theoretical rating.
Does dual-channel memory matter?
Yes. Two matching sticks in the right slots can substantially increase bandwidth.
Will the test slow down my computer?
Only briefly while it runs. All test memory is released at the end.
Related tools
See how memory fits the whole system
Benchmark CPU, memory and graphics together and find your bottleneck.