What is a stablecoin
Why the “digital dollar” is becoming payment infrastructure
When people hear the word stablecoin, many may first think of crypto assets. The impression is that they are part of the same group as highly volatile crypto assets like Bitcoin or Ethereum, and are things bought and sold on exchanges.
However, from the perspective of payment infrastructure, stablecoins are not just crypto assets.
This article is not for investing in stablecoins. It is a foundational map for understanding stablecoins as the intersection of payment infrastructure, monetary sovereignty, bank deposits, and AI payments.
A stablecoin is a digital payment unit designed to peg its value to a fiat currency such as the US dollar. Representative examples like USDT and USDC have been used as waiting capital for trades in the crypto asset market. Recently, however, they have come to be discussed in the context of broader payment infrastructure, such as cross-border remittances, corporate treasury management, on-chain payments, and AI agent payments.
What is important here is not to view stablecoins only as “crypto assets with stable prices.”
From another perspective, stablecoins are something like a digital dollar issued by the private sector. Of course, they are not real dollar bills, bank deposits, or central bank money. In many cases, the issuer holds cash, short-term government bonds, deposits, and other safe assets as reserve assets, and attempts to maintain a value close to 1 stablecoin = 1 dollar through that backing.
In other words, the essence of a stablecoin is not the blockchain itself.
The real question is, who issues it, what is it backed by, where can it be redeemed, which ledger does it run on, and who supports its credit.
Once you have this question in mind, news about stablecoins starts to look quite different.
The story that “USDC is used for AI agent payments” is not just about crypto asset payments. It is about a payment unit that is easy for machines to handle entering internet API billing. The story that “dollar-denominated stablecoins are used in emerging countries” is not just about a convenient means of remittance. It is about the digital dollar, rather than the local currency, entering daily payments. The story that “central banks are wary of stablecoins” is not just about crypto asset regulation. It is about bank deposits, monetary policy, monetary sovereignty, and reserve asset markets.
In this article, as an entry point for reading this medium in the future, I will organize what a stablecoin is.
There is no need to memorize difficult cryptographic technologies. What is needed first is to view stablecoins not just as a “type of crypto asset,” but as a digital liability issued by the private sector, or a private-money-like payment unit.
1. A stablecoin is a digital asset “designed to be stable”
First, let's clarify the term stablecoin.
A stablecoin is a digital asset designed to peg its value to a specific asset, mainly a fiat currency such as the US dollar. Although it has “stable” in its name, it does not mean that the “price is absolutely stable.” It only means that it is designed to maintain price stability.
This is important.
Depending on its design, a stablecoin maintains a price close to 1 dollar. However, if there are problems with the reserve assets, restrictions on redemption, market anxiety, regulatory issues, or if trust in the issuer is shaken, it may deviate from 1 dollar.
In other words, when looking at stablecoins, it is important not to think that they are “safe because the name is stable.”
What you should look at are the following points.
Who is the issuer?
What are the underlying assets?
Can it truly be redeemed at a 1-to-1 ratio?
Who holds the reserve assets?
Are there audits or attestations?
Which jurisdiction's regulations does it fall under?
Which blockchain does it run on?
What happens to holders if the issuer goes bankrupt?
The credibility of a stablecoin is not built on code alone. Rather, it is established through a combination of trust in the issuer, reserve assets, custodian banks, regulations, redemption rules, wallets, exchanges, and users.
In this regard, stablecoins are quite different from crypto assets like Bitcoin.
Bitcoin does not attempt to peg its value to a specific fiat currency. Its price fluctuates significantly in the market. On the other hand, dollar-denominated stablecoins derive their value from being usable at around one dollar. They are more likely to be used as payment units, idle funds, or settlement assets rather than as investment targets.
Stablecoins were born within the crypto asset market. However, their essence lies not in being "assets aimed at price appreciation," but in beingstable payment units that can be used in digital spaces.
2. Stablecoins are someone's liability
To understand stablecoins, the most important thing to realize is that in many cases, a stablecoin is someone's liability.
Cash is a liability of the central bank.
Bank deposits are liabilities of commercial banks.
E-money balances may be designed as claims against the issuing entity.
Stablecoins, too, should in many cases be understood as claims against the issuer or the associated mechanism.
In other words, a stablecoin is not "just a digital token." Behind it is a structure where someone promises that "this can be exchanged for one dollar" or "this has a value equivalent to one dollar."
For example, Circle, the issuer of USDC, describes USDC as a digital dollar backed by cash and cash equivalents, redeemable for US dollars on a 1-to-1 basis. This means that the credibility of USDC is supported by the issuer, reserve assets, redemption rules, and custodial arrangements.
What is important here is that stablecoins are different from bank deposits.
Bank deposits are used as settlement assets within the banking system and are linked to deposit insurance, banking regulations, and liquidity provision by the central bank. On the other hand, the design of a stablecoin varies depending on the issuer and the jurisdiction. There is no guarantee of deposit insurance. They are not central bank money either. How the issuer holds reserve assets and how holders can redeem them becomes extremely important.
If you overlook this difference, you will overestimate stablecoins.
Stablecoins are convenient. They operate 24/7. They are easy to handle programmatically. They are also suitable for cross-border digital payments. However, they are not "money that requires no trust in anyone." Rather, they aremoney where it is easy for it to become unclear what you are actually trusting.
When looking at a stablecoin, you should always think as follows:
Whose promise is this token?
What is that promise backed by?
Will that promise be kept even in a crisis?
Herein lies the essence of stablecoins.
3. Why are dollar-denominated stablecoins so strong?
There are stablecoins denominated in dollars, euros, yen, and other currencies. However, in reality, dollar-denominated stablecoins have an overwhelmingly strong presence.
The reason is simple: the demand for the US dollar is extremely strong in the global digital economy, the crypto asset market, and cross-border transactions.
For many countries and companies, the dollar is the common unit for international transactions. Trade, financial markets, commodity trading, capital flows, and foreign exchange reserves—the dollar is already at the center of the global financial infrastructure. Stablecoins are bringing that status of the dollar into the digital space.
The same applies to the crypto asset market. When buying and selling Bitcoin or Ethereum on an exchange, it is inconvenient to convert everything back to fiat currency. Therefore, dollar-pegged stablecoins are used as standby funds. Temporarily escaping from highly volatile crypto assets, moving funds to another exchange, or using them as collateral or liquidity in DeFi—dollar-denominated stablecoins are extremely convenient for these purposes.
Furthermore, dollar-denominated stablecoins are sometimes used by people who have difficulty accessing bank accounts or in regions where access to the dollar is restricted. Of course, this involves regulatory and legal issues. However, in reality, stablecoins are easily utilized as a means of digital dollar access.
Here, the issue of monetary sovereignty arises.
What happens if a dollar-denominated stablecoin becomes more convenient to use than a country's own currency? If daily payments, savings, price displays, and some inter-company settlements shift toward digital dollars, the central bank and government of that country may find it difficult to exert influence through monetary policy and capital controls.
In other words, the strength of dollar-denominated stablecoins is not merely the strength of the technology; it is the strength of the dollar itself.
It can be said that stablecoins are the network effect of the dollar placed on a blockchain. That is precisely why central banks and policymakers outside the United States are wary. This is a discussion about crypto asset regulation, but at the same time, it is also a discussion about the digitization of dollar hegemony.
4. What are stablecoins used for?
The uses for stablecoins are gradually expanding. Broadly speaking, there are five main current uses.
First, standby funds for crypto asset trading.
This is the oldest and most straightforward use. After selling highly volatile crypto assets, instead of immediately returning them to a bank account, they are held in dollar-denominated stablecoins. Waiting for the next trading opportunity, moving funds between exchanges—in the crypto asset market, stablecoins have become the foundation of liquidity.
Second, settlement units for DeFi and on-chain finance.
In financial transactions on the blockchain, such as lending, liquidity provision, derivatives, and collateral management, a unit with a stable price is required. It is difficult to use assets with large price fluctuations like Bitcoin or Ethereum as a standard for daily financial transactions. Therefore, stablecoins are used.
Third, cross-border remittances and international settlements.
Cross-border bank transfers take time, have high fees, and may pass through multiple correspondent banks. By using stablecoins, technically, value can be transferred across borders relatively quickly, 24 hours a day. However, actual usage involves each country's regulations, identity verification, conversion channels, and the recipient's wallet environment. Stablecoins are not a magic remittance tool, but they have the potential to reduce the friction of existing cross-border payments.
Fourth, corporate treasury management.
Some companies may use stablecoins for moving funds with overseas branches or business partners, on-chain transactions, and settlements for digital asset-related businesses. Being able to move funds between multiple countries and platforms without being bound by bank business hours is significant for corporate fund management.
Fifth, AI agents and machine-to-machine payments.
In scenarios where AI agents pay for APIs, MCP servers, web content, and other agents, small-amount, high-frequency, machine-readable payments are required. Stablecoins are well-suited for this domain because they are easy to handle programmatically and payment status is easy to verify. This is quite important as a new use for stablecoins.
Looking at it this way, stablecoins are no longer just "dollars inside crypto asset exchanges." What was born from the crypto asset market is spreading to cross-border payments, corporate fund management, and machine-to-machine billing.
However, as their use cases expand, their regulatory importance also increases. This is because the more they are used, the greater the impact when they fail.
5. Why is the revenue model of stablecoins so strong?
To understand stablecoins, the revenue model of the issuer is also important.
In a typical reserve-backed stablecoin, the issuer receives dollars from users and issues stablecoins. They hold the received dollars in cash, bank deposits, short-term government bonds, money market funds (MMFs), and so on. In an environment with interest rates, interest income is generated from those reserve assets.
On the other hand, many reserve-backed stablecoins are not designed to pay that interest directly to the holders. In other words, the issuer can use the interest income earned from the reserve assets as a source of revenue.
This is a very strong model.
The more users hold stablecoins, the more the issuer increases its reserve assets. As reserve assets increase, interest income also increases. Especially in a high-interest-rate environment in the U.S., the profitability of dollar-denominated stablecoin issuers rises significantly.
Here, stablecoins become not only a payment infrastructure but also an interest-bearing business.
However, this simultaneously attracts the attention of policymakers. If a stablecoin issuer holds a large amount of short-term government bonds, it could potentially affect the short-term financial markets. If large-scale redemptions occur during a crisis, they may have to sell off reserve assets, which could put stress on the market. While they may be convenient digital dollars from the user's perspective, from the perspective of the entire financial system, they exist across payments, short-term financial markets, and bank deposits.
Also, how an issuer earns revenue is related to user protection.
Is there a temptation to invest in higher-yield but riskier assets to earn interest income from reserve assets?
Are they holding assets with low liquidity?
Can they really be converted to cash when redemption requests are concentrated?
Is the management of reserve assets transparent?
Stablecoins are simple on the surface. You deposit one dollar and get one dollar's worth of tokens. However, behind that, there are very financial issues such as reserve asset management and liquidity management.
6. Where do the risks of stablecoins lie?
Stablecoins have risks that are just as important as their convenience.
First, there is reserve asset risk.
Whether a stablecoin can maintain a value of one dollar depends on the quality of the backing assets. If it is sufficiently backed by cash or short-term government bonds, trust is easily increased. On the other hand, if it includes high-risk assets, low-liquidity assets, or opaque assets, anxiety will spread during a crisis.
Second, there is redemption risk.
Can users really redeem stablecoins for one dollar? Who can redeem them directly? Can general users also request direct redemption from the issuer? Or do they have no choice but to sell them through an exchange? Will redemptions be suspended during a crisis? This is very important.
Third, there is run risk.
If anxiety about the issuer or reserve assets spreads, there is a possibility that users will try to redeem all at once. This is a phenomenon similar to a bank run. If the issuer sells a large amount of reserve assets, it could also affect the market. The larger stablecoins become, the more this risk becomes a problem for financial stability.
Fourth is operational risk.
Blockchains, smart contracts, wallets, custody, exchanges, and bridges. Stablecoins operate on top of a lot of technical infrastructure. If mistakes in private key management, smart contract bugs, chain failures, hacks, or bridge accidents occur, users may suffer losses.
Fifth is regulatory, sanctions, and AML risk.
Stablecoins move easily across borders. Therefore, there is a risk they will be used for money laundering, sanctions evasion, fraud, and illegal fund transfers. This is also why regulators have a strong interest in stablecoins.
Sixth is monetary sovereignty risk.
If dollar-denominated stablecoins are widely used in other countries, it could affect those countries' currencies and monetary policies. This is a serious issue, especially for emerging nations. If digital dollars, rather than the local currency, come to be used for savings and payments, unofficial dollarization may progress.
In short, the risks of stablecoins are not just about whether the price deviates from one dollar. Reserve assets, redemption, operations, regulation, financial stability, and monetary sovereignty are all intertwined.
7. How are stablecoins different from bank deposits?
To understand stablecoins, it is easiest to look at how they differ from bank deposits.
Bank deposits are claims against a bank. Depositors entrust money to a bank, and the bank uses those funds for lending and investment. Banks are regulated, follow capital and liquidity rules, and are connected to central banks and deposit insurance systems. Bank deposits are not only used for payments but also play a role in credit creation.
On the other hand, reserve-backed stablecoins are basically a model where the issuer holds the funds received in safe assets and issues tokens against them. Their primary function is not credit creation through lending like a bank. Rather, it is important that the issued stablecoins correspond to the reserve assets.
This difference is significant.
Bank deposits are a part of financial intermediation. Stablecoins are, in many cases, digital liabilities for payment, storage, and transfer.
Of course, as stablecoin issuers grow, they become deeply linked to short-term financial markets through the management of their reserve assets. However, this is different from a mechanism that supplies credit to the economy through lending, as bank deposits do.
That is why central banks and commercial banks are wary of stablecoins.
If stablecoins are used to replace bank deposits, funds may flow out of banks. If bank deposits decrease, it could affect banks' lending capacity and financial intermediation. Meanwhile, stablecoin issuers will come to hold large amounts of short-term government bonds, strengthening their ties to short-term financial markets.
In other words, stablecoins do not completely replace banks. However, they may take away some of the functions of bank deposits, especially the functions of payment, storage, and international transfer.
Herein lies the tension between stablecoins and banks.
8. How are stablecoins different from CBDCs?
Stablecoins and CBDCs are also often confused. This is because both appear to be digital money.
However, the two are fundamentally different.
A stablecoin is, in many cases, a digital liability issued by a private issuer. It is designed to peg its value to a fiat currency, but its credit is backed by the issuer, reserve assets, redemption rules, and regulations.
On the other hand, a CBDC is a digital currency issued by a central bank. If a retail CBDC is introduced, it could allow the general public to use digital central bank money directly. Just as cash is a liability of the central bank, a CBDC is also designed as a liability of the central bank.
This difference lies in the source of credit.
A stablecoin is credit in the issuer and reserve assets.
A CBDC is credit in the central bank and the national monetary system.
However, it is not a simple matter of a CBDC being superior to a stablecoin in every respect. CBDCs are difficult to design, and there are many issues such as privacy, impact on bank deposits, monetary policy, offline use, and competition with private payments. While stablecoins are private-led and tend to develop quickly, they face issues of credit and regulation.
In other words, stablecoins and CBDCs are not the same "digital money".
Each should be viewed as the digitalization of private money and central bank money respectively.
9. What is the difference between stablecoins and tokenised deposits?
Recently, not only stablecoins but also the term tokenised deposits has emerged.
This is a concept that makes bank deposits available on blockchains or distributed ledgers. While a stablecoin is a digital liability by a private issuer, tokenised deposits are based on the idea of tokenizing bank deposits themselves.
This difference is also important.
Stablecoins are closer to a movement to create digital payment units from outside the banking system.
Tokenised deposits are closer to a movement to place deposits that are inside the banking system onto a digital ledger.
This is why European policymakers and central bank officials sometimes prioritize tokenised commercial bank deposits over euro-denominated stablecoins. If bank deposits are tokenized, it may be possible to incorporate digital payments and programmability while maintaining bank intermediation.
Stablecoins, CBDCs, and tokenised deposits may look like similar terms, but each poses a different question.
Stablecoins are digital liabilities by private issuers.
CBDCs are the digitalization of central bank money.
Tokenised deposits are the digital ledgerization of bank deposits.
Depending on which of these three spreads, the control points of future payment infrastructure will change.
10. Seven questions for looking at stablecoins
When looking at news about stablecoins, it is easier to organize your thoughts by asking the following seven questions.
First, who is issuing it.
Is the issuer reliable? In which jurisdiction are they located? Are they regulated? Is there transparency? The credit of the issuer is directly linked to the credit of the stablecoin itself.
Second,what is it backed by?.
Is it cash? Bank deposits? Short-term government bonds? Money market funds? Does it include corporate bonds or other assets? The quality of the reserve assets determines the stability of the stablecoin.
Third,who can redeem it directly?.
Can 1 stablecoin really be exchanged for 1 dollar? Can general users also redeem it directly? Is it only for institutional investors? Are you forced to sell it on an exchange? The redemption design is extremely important.
Fourth,which ledger does it run on?.
Ethereum, Solana, Base, or other blockchains. Depending on which chain it runs on, the fees, speed, security, developer ecosystem, and use cases will change.
Fifth,where is it being used?.
Is it only within cryptocurrency exchanges? Is it used in DeFi? Is it used for corporate payments? Is it used for remittances? Is it included in AI agent payments? It is important to look at the use cases.
Sixth,what happens in a crisis?.
What happens if a bank run occurs? Can the reserve assets be sold? What happens if there is a problem with the issuer or the custodian bank? What happens if the blockchain stops? You need to look at stress scenarios, not just normal times.
Seventh,who is earning the revenue?.
Who takes the interest income from the reserve assets? Who gets the remittance fees? Where does the value remain—with the wallet, the exchange, the issuer, the chain, or the payment provider? A stablecoin is a payment method, but it is also a revenue model.
By looking at these seven points, you can understand stablecoins not just as a 'convenient digital dollar,' but as payment infrastructure.
11. Why are stablecoins important now?
Stablecoins are important now because multiple trends are converging.
First,the digitalization of the dollar. Dollar-denominated stablecoins make it easier to transfer dollars on the blockchain. This has the potential to expand the international influence of the dollar into the digital space.
Second,friction in cross-border payments. International remittances can still be slow, expensive, and complex. Stablecoins have the potential to reduce the friction of existing payments in this area.
Third,foundational assets for on-chain finance. DeFi, RWA, tokenized government bonds, and on-chain securities settlement. As these expand, a stable unit of payment becomes necessary.
Fourth,AI agent payments. In a world where AI makes small, high-frequency payments to APIs and MCP servers, machine-readable payment units like stablecoins become strong candidates.
Fifth,the issue of monetary sovereignty. As dollar-denominated stablecoins spread in other countries, governments and central banks will be forced to consider the impact on their own currencies, bank deposits, and monetary policy.
In short, stablecoins are no longer just an internal issue for the crypto asset market.
They are beginning to shift into a space where currency, banking, cross-border payments, AI, capital markets, and national strategy intersect.
12. Perspective on viewing stablecoins in this medium
When looking at stablecoins in this medium, 'Payment Infrastructure Observation,' what I want to emphasize is not price or speculation.
What I want to see is the infrastructure that lies beneath.
Whose currency influence do stablecoins expand?
What reserve assets do issuers hold?
Do they siphon funds away from bank deposits?
Which frictions in cross-border payments do they reduce?
How are they used for AI agents and API billing?
How do they compete with tokenized deposits and CBDCs?
Which players earn the revenue?
Where do regulators draw the line?
The essence of stablecoins is not the simple question of 'whether crypto assets will become payments.'
The real question is, who issues, redeems, regulates, and monetizes the money used in digital space?.
With this question in mind, stablecoins become a very important theme. This is because they are not merely a new means of payment, but an intersection connecting private money, bank deposits, central bank money, dollar hegemony, and AI payments.
Conclusion—Viewing stablecoins not as crypto assets, but as a 'redesign of private money'
What is a stablecoin?
My answer is this.
A stablecoin is a privately issued digital payment unit that brings the value of fiat currency or similar assets into digital space, allowing it to be transferred on ledgers such as blockchains in most cases.
It is a convenient digital dollar.
At the same time, it is someone's liability.
It is a means of payment.
At the same time, it is a reserve asset business.
It is a tool for cross-border payments.
At the same time, it is a matter of monetary sovereignty.
It is a candidate for AI agent payments.
At the same time, it is financial infrastructure that requires regulation and oversight.
Therefore, I think it is superficial to view stablecoins only as a type of crypto-asset.
What we really need to look at is which ledger a stablecoin operates on, what reserve assets back it, what regulations it is subject to, and what use cases it penetrates.
The spread of stablecoins does not simply mean that new tokens are being used. It means that competition is intensifying over whose money will become the standard in the digital space.
Is it USDC? Is it USDT? Is it a euro-denominated stablecoin? Is it tokenised deposits? Is it a CBDC? Or will they coexist by serving different purposes?
This question is unavoidable when looking at the future of payment infrastructure.
A stablecoin is not just a crypto-asset.
It is a question of who will design private money in the digital age.