A new guide measures the two work functions behind browser proof-of-work challenges in the same WebAssembly runtime a browser uses. One SHA-256 probe costs 0.3862 microseconds; one Argon2id probe at 19 MiB costs 71.2 milliseconds - a ratio of about 184,000 to one. That inverts the difficulty settings: the memory-hard tier runs at 2 to 4 bits where the compute tier needs 20 or more, and pushing the compute tier to 26 bits costs a real user 25.9 seconds while a rented GPU farm barely notices. A 12-minute flood on 7 August, 67,751 challenges to 923 addresses across 525 networks in 97 countries, produced zero incorrect proofs - and the article is explicit that this shows nobody attempted the work, not that nobody could.