Bitcoin CoinJoin Cost Calculator: Wasabi vs Whirlpool Fees

CoinJoin Cost Overview

Every CoinJoin transaction has two cost components: the coordinator fee (paid to the service that orchestrates the mixing round) and the mining fee (paid to Bitcoin miners for on-chain block space). The total cost of mixing depends on which implementation you use, how much you are mixing, and the current fee rate on the Bitcoin network.

Wasabi Wallet (using the WabiSabi protocol) and Whirlpool (originally built by Samourai Wallet, now maintained by Ashigaru) take fundamentally different approaches to pricing. Wasabi charges a percentage-based coordinator fee, while Whirlpool charges a flat one-time fee per pool tier. This difference creates distinct cost profiles depending on the size of your UTXOs.

For a broader comparison of CoinJoin implementations including JoinMarket, see our CoinJoin implementations comparison.

Wasabi WabiSabi Fee Breakdown

Wasabi Wallet 2.0 introduced the WabiSabi protocol, which replaced the original ZeroLink CoinJoin model. WabiSabi allows variable input and output amounts within a single round, eliminating the fixed-denomination constraint of earlier designs.

Coordinator Fee

The coordinator fee is 0.3% of the input value for any UTXO above 0.01 BTC (1,000,000 sats). Inputs of 0.01 BTC or less pay zero coordinator fee under the "plebs don't pay" policy. This fee is charged only on the first round: subsequent remixes are free of coordinator fees.

If you receive already-coinjoined bitcoin and re-register it, the coordinator fee is also waived. This means the effective cost of achieving a high anonymity set through multiple rounds depends primarily on mining fees rather than coordinator fees.

Mining Fees

In WabiSabi, each participant pays mining fees proportional to the block space their registered inputs and outputs consume. A single input costs approximately 68 virtual bytes (vB) and a single output costs approximately 31 vB. With one input and one output, your share of the mining fee is roughly 100 vB multiplied by the current fee rate.

Unlike Whirlpool, Wasabi charges mining fees on every remix round. At low fee rates (under 10 sat/vB), this cost is negligible. During fee spikes, the cumulative mining cost across multiple remixes can become significant.

Current Status

zkSNACKs, the company behind Wasabi Wallet, discontinued its CoinJoin coordinator service on June 1, 2024, citing regulatory uncertainty. Wasabi Wallet remains functional as open-source software, and third-party coordinators (such as Kruw) now operate WabiSabi coordination services. Fee structures may vary by coordinator.

Whirlpool Fee Breakdown

Whirlpool uses a fixed-denomination pool model. Users select a pool tier, and a preparatory transaction called Tx0 splits their input into equal-sized premix UTXOs matching the pool denomination. The coordinator fee is a one-time flat amount per Tx0, regardless of how many premix UTXOs are created.

Original Samourai Whirlpool Pool Tiers

Before Samourai Wallet was seized by the DOJ in April 2024, Whirlpool offered four pool tiers. In March 2021, Samourai applied a permanent 30% fee reduction to the two largest pools:

Ashigaru Whirlpool Pool Tiers

In June 2025, Ashigaru relaunched Whirlpool with a new coordinator and two pool tiers, both at 5% entry fees:

• 0.25 BTC pool: 0.0125 BTC fee (1,250,000 sats)
• 0.025 BTC pool: 0.00125 BTC fee (125,000 sats)

Tx0 Premix Transaction

The Tx0 is a preparatory transaction that splits your selected UTXO into pool-sized premix outputs. It also creates a coordinator fee output and a change output for any remainder. This change output (sometimes called "doxxic change") is not mixed and can potentially be linked back to the original UTXO through address clustering techniques.

Mining fees for the Tx0 transaction depend on its size, which scales with the number of premix outputs. A Tx0 creating 5 premix outputs is roughly 300 vB, while one creating 20 outputs is roughly 760 vB.

Free Unlimited Remixes

Whirlpool's most significant cost advantage is its remix model. Once a UTXO has been through its initial mix, it can participate in unlimited additional mixing rounds at zero cost. Remixing UTXOs ("free riders") pay neither coordinator fees nor mining fees. Fresh participants in each round cover the entire transaction's mining cost.

Coordinator Fee Comparison by UTXO Size

The following table compares the coordinator or pool fee (excluding mining fees) for mixing different UTXO sizes. For Whirlpool, the "optimal pool" column shows the lowest-cost pool choice for each amount using the original Samourai tiers. The flat fee is paid once per Tx0 regardless of how many premix UTXOs are generated.

A clear pattern emerges: Wasabi's percentage-based fee is significantly cheaper for small and moderate UTXOs, while Whirlpool's flat fee becomes more efficient at larger amounts. The crossover point where Whirlpool's 0.05 BTC pool fee (175,000 sats) costs less than Wasabi's 0.3% is approximately 0.58 BTC.

Total Estimated Cost Including Mining Fees

Mining fees depend on the network fee rate and vary significantly. The following estimates use two representative fee environments: 10 sat/vB (normal conditions) and 50 sat/vB (congested network). Wasabi mining fees are estimated at ~100 vB per round. Whirlpool estimates include Tx0 costs (variable by output count) and first-mix costs (~250 vB per fresh participant).

Note: Whirlpool costs for 0.5 and 1 BTC use the 0.05 BTC pool for optimal pricing. Using the 0.5 BTC pool would cost significantly more (3.5% pool fee). Mining fee estimates are approximate and vary with network conditions, round composition, and the number of premix UTXOs created.

Effective Privacy Cost per BTC Mixed

The "effective privacy cost" measures the total fee as a percentage of the amount being mixed. This metric helps compare value across implementations. At normal fee rates (10 sat/vB), the cost profiles diverge sharply based on UTXO size:

• Under 0.01 BTC: Wasabi is effectively free (0.1% mining only). Whirlpool costs 5%+ due to its flat pool fee, making it impractical for very small UTXOs.
• 0.01 to 0.5 BTC: Wasabi is consistently cheaper at a flat 0.3% plus minor mining fees. Whirlpool ranges from 3.6% (0.05 BTC) down to 0.41% (0.5 BTC), improving as the flat fee is amortized over more premix UTXOs.
• Above ~0.58 BTC: Whirlpool's 0.05 pool fee (175,000 sats) becomes cheaper as a percentage than Wasabi's 0.3%. At 1 BTC, the coordinator-only cost is 0.175% for Whirlpool versus 0.3% for Wasabi.
• With many remixes: Whirlpool's advantage grows because remixes are completely free (no mining fees for remixers). Wasabi's remix mining costs accumulate with each additional round.

For users who plan to leave their coins remixing for extended periods to build a large anonymity set, Whirlpool's zero-cost remix model offers a meaningful long-term savings, especially at higher fee rates. For users who want a single mix with minimal cost, Wasabi's percentage-based model is more predictable and cheaper for most UTXO sizes under 0.5 BTC.

Multi-Round Remix Cost Comparison

The cost divergence between implementations becomes more pronounced over multiple remix rounds. Consider mixing 0.1 BTC through 10 rounds at 20 sat/vB:

• Wasabi: 30,000 sats coordinator fee (first round only) + 2,000 sats mining per round x 10 rounds = 50,000 sats total (0.5%)
• Whirlpool: 175,000 sats pool fee + ~5,000 sats mining for Tx0 and first mix + 0 sats for 9 remixes = ~180,000 sats total (1.8%)

At 0.1 BTC, Wasabi remains cheaper even after 10 rounds. The math shifts at larger amounts. For 1 BTC through 10 rounds at 20 sat/vB:

• Wasabi: 300,000 sats coordinator + 2,000 sats x 10 = 320,000 sats (0.32%)
• Whirlpool (0.05 pool): 175,000 sats pool fee + ~25,000 sats mining for Tx0 and first mixes + 0 for remixes = ~200,000 sats (0.2%)

At 1 BTC, Whirlpool is cheaper both initially and over many rounds. The crossover point moves lower as the number of remix rounds increases, because Wasabi accumulates mining fees while Whirlpool does not.

Which is More Cost-Effective

The optimal choice depends on three factors: UTXO size, desired number of remix rounds, and current network fee rate.

Choose Wasabi WabiSabi when:

• Mixing small UTXOs under 0.5 BTC
• Mixing UTXOs of 0.01 BTC or less (zero coordinator fee)
• You want a single mix round with minimal cost
• You prefer variable-amount outputs without fixed denominations
• You want to avoid the common input heuristic issues created by Whirlpool's Tx0 change output

Choose Whirlpool when:

• Mixing large amounts above 0.5 BTC (especially in the 0.05 pool)
• You plan to leave UTXOs remixing for days or weeks to maximize your anonymity set
• Network fee rates are high and you want to avoid per-round mining costs
• You prefer Whirlpool's deterministic 5-input/5-output transaction structure

For a comparison of CoinJoin versus PayJoin as alternative privacy approaches, see our CoinJoin vs PayJoin comparison.

Current Availability

The CoinJoin ecosystem has undergone significant disruption since early 2024. In April 2024, the U.S. Department of Justice arrested Samourai Wallet's founders and charged them with money laundering and operating an unlicensed money transmitting business. The founders later pleaded guilty and were sentenced to four and five years in prison respectively. Samourai's coordinator was seized and Whirlpool went offline.

In June 2024, zkSNACKs voluntarily shut down its Wasabi Wallet CoinJoin coordinator, citing a need for greater regulatory certainty. Wasabi Wallet continues to function with third-party WabiSabi coordinators, but liquidity and round frequency depend on which coordinator you connect to.

In June 2025, the Ashigaru project relaunched Whirlpool with a new coordinator, two pool tiers (0.025 and 0.25 BTC at 5% entry fees), and a desktop application called Ashigaru Terminal. This restored Whirlpool mixing to the Bitcoin ecosystem, though with different pool sizes and fee structures than the original Samourai implementation.

Users considering CoinJoin should evaluate the current legal landscape in their jurisdiction. For a broader overview of Bitcoin privacy tools and techniques, see our research on the Bitcoin privacy landscape in 2026 and transaction graph privacy defenses.

Frequently Asked Questions

How much does a CoinJoin cost on Wasabi Wallet?

Wasabi Wallet's WabiSabi protocol charges a 0.3% coordinator fee on inputs above 0.01 BTC, plus mining fees of roughly 100 vB per round. Inputs of 0.01 BTC or less pay zero coordinator fee. Remixes are free of coordinator fees but still incur mining costs. For example, mixing 0.1 BTC costs approximately 31,000 sats (~0.31%) at normal fee rates. Fees may vary by third-party coordinator since zkSNACKs shut down its coordination service in June 2024.

How much does Whirlpool mixing cost?

Whirlpool charges a one-time flat pool fee per Tx0 transaction. Under the original Samourai tiers, the 0.05 BTC pool charged 175,000 sats (3.5%) and the 0.5 BTC pool charged 1,750,000 sats (3.5%). Ashigaru relaunched Whirlpool in June 2025 with a 0.025 BTC pool at 125,000 sats (5%) and a 0.25 BTC pool at 1,250,000 sats (5%). After the initial mix, all subsequent remixes are completely free: no coordinator fee and no mining fee for remixing UTXOs.

Is Wasabi or Whirlpool cheaper for mixing Bitcoin?

It depends on the amount. For UTXOs under 0.5 BTC, Wasabi is cheaper due to its 0.3% fee versus Whirlpool's flat pool fee. For amounts above approximately 0.58 BTC, Whirlpool's flat fee (using the 0.05 BTC pool) is cheaper as a percentage. For users who want many remix rounds, Whirlpool has an additional advantage because its remixes are entirely free, while Wasabi's remixes still cost mining fees.

What is the Tx0 transaction in Whirlpool?

Tx0 is a preparatory transaction that splits your selected UTXO into equal-sized premix outputs matching the chosen pool denomination. It also creates an output for the coordinator fee and a change output for any remainder that does not fit into a full pool-sized UTXO. The Tx0 mining fee varies based on the number of premix outputs created. A Tx0 producing 5 premix outputs is approximately 300 virtual bytes, while one producing 20 is approximately 760 virtual bytes.

Are CoinJoin remixes free on both Wasabi and Whirlpool?

Both implementations waive coordinator fees on remixes, but they differ on mining fees. Whirlpool remixes are completely free: remixing UTXOs ("free riders") contribute no mining fee to the transaction, as fresh participants cover all miner costs. In Wasabi WabiSabi, remixes are free of coordinator fees but you still pay your proportional share of the mining fee (~100 vB per round). Over many rounds, this difference becomes significant.

Can I still use Wasabi CoinJoin after zkSNACKs shut down its coordinator?

Yes. Wasabi Wallet is open-source software that supports connecting to third-party WabiSabi coordinators. After zkSNACKs discontinued its coordinator on June 1, 2024, community-operated coordinators such as Kruw have continued to run WabiSabi rounds. The wallet functions normally for sending and receiving bitcoin regardless of coordinator availability, but CoinJoin requires an active coordinator with sufficient liquidity.

What is doxxic change in Whirlpool?

Doxxic change is the leftover change output from Whirlpool's Tx0 transaction. Because Whirlpool uses fixed pool denominations, any amount that does not divide evenly into pool-sized outputs becomes unmixed change. This change can be linked to the original UTXO through address clustering analysis, partially undermining the privacy gained from mixing. Managing doxxic change carefully (spending it separately or mixing it in a smaller pool) is an important part of Whirlpool operational security.

This tool is for informational purposes only and does not constitute financial advice. Fee structures are based on publicly documented coordinator policies and may change. Mining fee estimates are approximate and vary with network conditions. The legal status of CoinJoin services varies by jurisdiction: consult local regulations before using privacy tools. Always verify current fees with the specific coordinator you plan to use.