How does AES hardware support affect RandomX hashrate?

AES hardware support usually helps your CPU mine RandomX faster because it speeds up the AES operations RandomX uses. Without it, mining software must do that work through slower software routines, although the size of the hashrate difference depends on your processor and mining setup. For browser mining, there is another catch: your browser may not let the miner use those hardware instructions directly.

What AES does inside RandomX

AES stands for Advanced Encryption Standard, a widely used method for encrypting data. Many processors include special instructions that handle AES operations much faster than ordinary software can.

RandomX, Monero’s mining algorithm since November 2019, uses AES-based routines to help generate and process its working data. Here, AES is part of the mining calculation, not a step that encrypts your wallet.

Your hashrate is the number of mining calculations your device completes each second. When hardware handles the AES parts more quickly, your CPU can spend less time on each calculation, potentially increasing that rate.

On Intel and AMD processors, this feature is commonly called AES-NI. On ARM processors, such as those in many phones and newer laptops, comparable support comes through AES instructions in the processor’s cryptographic extensions.

Why there is no fixed speed boost

AES support removes one possible bottleneck, but RandomX does much more than AES work. It also runs changing sequences of instructions and makes frequent memory accesses.

Your final hashrate therefore depends on several things:

• CPU cache: Small, fast memory inside your processor. RandomX needs roughly 2 MB of L3 cache per mining thread for efficient operation.
• Memory performance: How quickly your CPU can retrieve the data it needs.
• Mining mode: Fast mode uses a 2,080 MB dataset, while light mode uses a 256 MB cache and requires more computation.
• Cooling and power limits: A hot or power-limited processor may slow itself down.
• Software quality: Your miner must recognize and use the available AES instructions.

That means you should not assume AES support makes every processor twice as fast, or guarantees any other fixed increase. It can make a substantial difference, but only a controlled benchmark can show the difference on your machine.

Why browser mining is different

A processor having AES instructions does not mean a web-based miner can use them.

Browser miners commonly run through WebAssembly, a format that lets compiled code run inside a browser’s restricted environment. Standard WebAssembly does not directly expose the CPU’s AES instructions in the same way native mining software can.

Browsers also provide encryption tools, but those tools are not a practical replacement for the specific AES operations deep inside RandomX’s mining loop.

So an “AES supported” label on your CPU is not enough to predict your browser hashrate. The browser, the miner’s implementation, and its memory limits all matter. Native mining benchmarks may not reflect what you will see in a browser.

How you can check the effect

Check your processor’s specifications for AES-NI or ARM AES support. For a native miner, also check its startup messages for confirmation that hardware AES is enabled.

If your miner allows a software-AES comparison, keep the thread count, memory settings, and test duration unchanged. Compare sustained results after temperatures settle, not just the first few seconds.

The bottom line

AES hardware support is valuable for RandomX, but it is only one part of mining performance. For browser mining especially, judge the miner by measured, sustained hashrate—not simply by whether your CPU supports AES.