Data anchoring and timestamping · Comparison
Hedera Consensus Service vs KAS Anchor API vs OriginStamp
3 products compared side by side: what you pay for with each one first, then the five access facts, entry prices, recorded plan limits and the bottom line of each review. The evidence note under the table says how each product was checked.
Side by side
| Metric | Hedera Consensus Service | KAS Anchor API | OriginStamp |
|---|---|---|---|
| What you're paying for | Worth the priceOrdered, consensus-timestamped records on a public ledger at a published $0.0008 per message, with no contract or vendor account. | Saves engineering timeAnchor private-chain block hashes or other data to the Kaia public chain through a managed API, without running a Kaia node. | Saves engineering timeAnchor your hashes to Bitcoin and Ethereum through one REST call, without running wallets, nodes or Merkle batching yourself. |
| Overall score | 4.8Best | 1.5 | 3.8 |
| Free option | Paid only | –Not measured | –Not measured |
| Card to start | –Not measured | –Not measured | –Not measured |
| Getting access | Self-serve | Sales call required | Sales call required |
| Starter priceCheapest paid plan | $0.0008/message | –Not measured | –Not measured |
| Pricing model | Usage-based | Custom quote | Custom quote |
| Pricing page | Public prices | Prices hidden | Prices hidden |
| What it anchors to | Hedera public ledger (messages on a topic) | Kaia mainnet (one transaction per payload) | Bitcoin and Ethereum (Merkle root per batch) |
| Billing unit | $0.0008 per message, paid in HBAR | Pay as you go by anchoring cycle and usage, by contact | Offer based on timestamps and proofs |
| Free option | Testnet only | Not stated for the Anchor API | Free web tool for single proofs; test API key on request |
| Reference scenario (100,000 hashes/mo) | $80, one hash per message, computed | Priced by sales | Priced by sales |
| Proof you keep | No proof file; records on mirror nodes | Transaction hash per payload | Downloadable certificate or raw proof |
| Verify without the vendor | Open-source mirror node you can run | Not described | Manual steps documented |
| Only the hash leaves your systems | Yes, you choose the message content | Yes, you choose the payload | Yes |
| Qualified timestamps (eIDAS) | No | No | eIDAS compatibility on request |
| SOC 2 / ISO 27001 | Node data centres must be SOC 2 Type 2 | Not stated | Not stated |
| API and webhooks | SDKs, mirror node REST and gRPC; no webhooks | REST API and caver SDK extensions; no webhooks | REST API, batch hashes, webhooks |
| SSO | Not applicable (key-based accounts) | Not listed | Not listed |
| Bottom line | From its public pages, HCS is the cheapest way here to put hashes on a public ledger at a price you can compute. You build the proof handling yourself, and there is no plan, contract or vendor audit report. | From its public pages, the KAS Anchor API is a managed route to anchor payloads on Kaia, now run by AhnLab Blockchain Company. Price, proofs and verification guidance are not on the pages. | From its public pages, OriginStamp is a long-running anchoring API with two chains, batching and webhooks. The price is an offer, and a few docs pages describe an older anchoring method. |
Evidence: Hedera Consensus Service: facts checked 2026-10-15 from its public sign-up and pricing pages, no completed hands-on run; KAS Anchor API: facts checked 2026-10-15 from its public sign-up and pricing pages, no completed hands-on run; OriginStamp: facts checked 2026-10-15 from its public sign-up and pricing pages, no completed hands-on run. Prices in USD as listed, excluding tax. "–" means not recorded.
When to pick each
In the words of each review, with the date its facts were checked.
From our Hedera Consensus Service review
Checked Oct 15, 2026- Pick Hedera Consensus Service when
- You want a published per-message price and full control of what you anchor.
- Pick OriginStamp when
- You want Merkle batching, Bitcoin and Ethereum anchors and a proof per hash handled by the vendor.
From our Hedera Consensus Service review
Checked Oct 15, 2026- Pick Hedera Consensus Service when
- You want a fee you can compute from public pages, without a contract.
- Pick KAS Anchor API when
- You build on Kaia and want anchoring set up through a managed API account in Korea.
From our KAS Anchor API review
Checked Oct 15, 2026- Pick KAS Anchor API when
- You build on Kaia or a private chain and want anchoring through a managed Korean API.
- Pick Hedera Consensus Service when
- You want a published fee per message and no contract.
From our KAS Anchor API review
Checked Oct 15, 2026- Pick KAS Anchor API when
- Your anchors belong on Kaia and your billing should run through a Korean operator.
- Pick OriginStamp when
- You want Merkle batching, proof files and anchors on Bitcoin and Ethereum.
From our OriginStamp review
Checked Oct 15, 2026- Pick OriginStamp when
- You want Bitcoin and Ethereum anchors with Merkle batching handled for you, plus a proof per hash.
- Pick Hedera Consensus Service when
- You want a published per-message fee ($0.0008) and can manage HBAR and your own batching.
Entry price
Baseline: each product's cheapest paid plan, per month. Included usage differs, so read the line under each price.
- Hedera Consensus ServiceMainnet, pay per transaction$0.0008/messageConsensusSubmitMessage; first 100 payload bytes included; paid in HBAR at the live rate
- Topic creation $0.01
- Account creation $0.05
- Messages up to 1,024 bytes
- BatchTransaction $0.001 plus each inner transaction
- KAS Anchor APIKAS API Starter$300/moGeneral KAS API plan: 100,000 requests a day
- Ticket-based support
- Overuse billed at the plan rate per request × 120%
- OriginStampTimestamping APIContact salesPrice depends on the number of timestamps and proofs
- Free test API key on request
- Several SHA-256 hashes per request
- Webhooks for tree and proof events
- Development API server
Prices as listed on each pricing page, in USD per month, excluding tax. Observed: Hedera Consensus Service 2026-10-15, KAS Anchor API 2026-10-15, OriginStamp 2026-10-15.
Which one fits
- If you need to start today without a sales call
- Hedera Consensus ServiceSelf-serve sign-up; the only one here you can use right after signing up.
- Lowest starter price
- KAS Anchor API$300/mo. Hedera Consensus Service and OriginStamp list no comparable paid price.
- Highest overall score
- Hedera Consensus Service4.8/10 (Fair). The review shows the score breakdown and the run behind it.
Picked by fixed rules from the table above, not by hand. How we score
Full reviews
Add a product
Search by product name or by what it does, such as “email” or “feature flags”. 1 more fits in this comparison.