Read any Hedera Consensus Service topic: the ordered message stream, running hash, SHA-256 timestamp proofs, oracle feed freshness, HIP-991 monetized topics and a DID resolver.
HCS assigns every message an immutable consensus timestamp and sequence number. The proof tool re-hashes message content so anyone can confirm it matches the on-chain record without trusting this site.
Feed freshness shows whether a topic is still publishing on schedule, and HIP-991 topics are read with their fee schedule — useful when a feed or a data marketplace is priced per message.
HCS is a public, ordered, timestamped message log on Hedera. Applications submit messages to a topic and the network assigns each one a consensus timestamp and order that cannot be changed afterwards — which is what makes it useful for audit trails, oracles and proofs.
Open a topic, pick a message and generate its SHA-256 proof. Anyone can re-hash the same content and compare it against the on-chain record, so you can prove a message existed at that exact consensus time without trusting this site.
Topics are identified as 0.0.x. Anybody can read a public topic, but only holders of the submit key can write to it. HCS HQ shows the memo, the submit key and the message count for any topic you paste.
Yes, if you submit the file's hash. Because the consensus timestamp is immutable, a matching hash proves the exact content existed no later than that moment — the basis of timestamping and notarisation on Hedera.
This is one of 22 free Hedera apps in Hedera HQ — live mainnet data, no wallet and no sign-up.