Is a Crypto Address Case Sensitive [Bitcoin and Ethereum Address]?

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A man in a suit standing next to a bitcoin, addressing the case sensitivity of crypto.
Table of Contents
A man in a suit standing next to a bitcoin, addressing the case sensitivity of crypto.

Key Takeaways:

  • Bitcoin addresses can be case sensitive, depending on their type, older types of Bitcoin addresses are case sensitive, while newer types are not case sensitive
  • Ethereum addresses are not case sensitive, both uppercase and lowercase versions of an Ethereum address represent the same address
  • Copying and pasting crypto addresses or using QR codes is recommended to minimize the risk of mistyping and potential loss of funds

Is a Crypto Wallet Address Case Sensitive?

Capitalization matters in crypto addresses. 

They can be case sensitive, but some address types aren’t case sensitive. 

Crypto addresses are another digital information you can type in on computers like URLs. URLs are also case sensitive, so the lower and upper case versions count as two separate addresses. The same principle applies to crypto addresses. 

Case sensitivity can make it hard to type addresses correctly. Not only do you have more characters possible, because of their length of up to 62 characters there is a risk to mistype one character. Here, your funds might be lost forever. 

There are a lot of security measures which were developed over time, so they minimized the risk of errors as much as possible. 

Errors are minimized but not impossible, therefore you should always double check any cryptocurrency address before you send your funds. One quick tip you should always apply is to copy and paste the address. 

This way you will always enter the addresses correctly. If you type them manually or write them down to use them later, always be concentrated and careful. These precautions will help you avoid massive mistakes in the future.

Are Bitcoin Addresses Case Sensitive?

Bitcoin addresses can be case sensitive, but this depends on their type. 

These addresses were developed and extended in functionality. 

This leads to a situation where we have now multiple types of addresses. Some of them are case sensitive and some are not case sensitive. The older types of Bitcoin addresses are case sensitive. 

Because this was a factor prone to errors, the developers introduced newer types which aren’t case sensitive anymore. If you use these older types, then you have to be cautious because the letter casing has to be exactly as it appears in the blockchain. 

If you just change the casing of one letter, the address gets wrong. Here, your funds can be lost, but not always. 

There are two scenarios that can happen. In the first one, there is a security measure which prevents you from sending your funds to an incorrect address. 

There is always a checksum mechanism which calculates a checksum of the address to validate if it is an authentic address. If this calculation results in a wrong checksum, the transaction will not be approved and your funds will not move. 

In the other scenario, the wrong address is not the one you intended to send your funds to, but it is still a valid address. This would apply to if someone else creates the address or it is another address which wasn’t derived from a private key yet. 

If someone else created it already and you won’t know who it is you probably won’t get your coins back. As long as you know who this address belongs to, then you can try to ask for a refund. 

If the address is valid but wasn’t derived from a private key yet, the transaction is still processed and your money is lost forever. Because of this risk you should always double-check your addresses before you send your funds.

How Are the Different Bitcoin Address Formats Case Sensitive?

There are four main address types in Bitcoin. 

We have Legacy, Script, SegWit and Taproot formats. 

A Bitcoin address is an alphanumeric string representing a destination for Bitcoin payments. All four formats differ in their prefixes, character length, and their case sensitivity. 

The two older ones, Legacy and Script, are case sensitive. This means that they use upper- and lowercase lettering in their addresses. 

Legacy addresses start with a “1”, Script addresses (also known as nested SegWit addresses) start with a “3”. They both comprise 34 characters and use upper- and lowercase letters. This makes them more prone to typing errors. 

The both newer types SegWit (also known as native SegWit addresses) and Taproot use the newer Bech32 encoding scheme with 42-62 characters. This encoding works without case sensitivity. 

The older addresses used the Base58 encoding scheme, which included case lettering. Bech32 addresses don’t use mixed case lettering. The developers introduced this to minimize the risk of mistyping older addresses. 

Bitcoin addresses also don’t use the characters 0 (zero), O (capital o), l (lower L) and I (capital i) because in some fonts they are displayed identically.

Are Bitcoin Public Keys and Private Keys Case Sensitive?

Bitcoin public keys and private keys are not case sensitive. 

Private keys can be case sensitive if you want them to be displayed in such a format. 

Here, you have the option to decide if you want them to be displayed this way. Private keys are randomly generated 256-bit numbers displayed in digits only. Basically, you can pick a number between 0 and 2^256. 

This number is displayed in hexadecimal notation. This notation uses the letters A to F besides 0 – 9, so there are no mixed case letters. 

You can decide to display this private key in the so-called “Wallet Import Format“ (WIF) to make it readable for wallets to import. Here, a SHA256 hash algorithm is used together with the Base58 encoding to change the key to the WIF-format. 

The Base58 encoding uses case lettering so this way a private key can be displayed with case sensitive characters. A public key, on the other hand, is always stored in hexadecimal notation. This key derives from the private key. 

The private key is converted through elliptic curve multiplication into the public key. The result is another hexadecimal number acting as the public key. Therefore, it has no mixed case lettering and is stored only in digits. You cannot convert it into other display formats.

Therefore, only the private key can be displayed with case lettering if wished. The public key can further generate an address which can be case sensitive.

Are Ethereum Addresses Case Sensitive?

Ethereum addresses are not case sensitive. 

Compared to Bitcoin, you don’t have to take mixed case letters into account and this potential risk is never an issue. 

These addresses are formatted as hexadecimal numbers, so as with Bitcoins private or public keys, the case lettering does not matter. There is one special function about Ethereum addresses, as you can write them in lowercase or uppercase letters. 

Both will work as the same address, but they both provide a different functionality even if they are equal. 

If you use the lowercase version of your address, this version will not be checksummed, meaning you won’t have any verification if your address you typed in is valid. This could be a potential risk as you could lose your ETH. 

The version with uppercase letters is always checksummed. This means that it will be verified if it is correct. This is a security feature you should use. It is recommended to always use the uppercase letter version of Ethereum addresses.

Is There Another Way to Copy and Paste Crypto Addresses?

Another common way is to use addresses as QR codes. 

Because of the potential risk with mistyping long strings of random characters, this option is also provided for wallet addresses. 

With a QR code, people can use it conveniently and easily. You can scan and photograph it to auto-start transactions for your cryptocurrencies. This makes transactions not only more secure but also faster. 

Other than that, most crypto wallets provide copy and paste buttons to help you conveniently copy addresses. This way, you don’t have to mark the address manually to copy it. 

Even if copying this way is much safer than typing it manually, there is also a risk of not highlighting the entire string before you copy it. It can easily happen that you highlight everything except the last character. 

This way you can easily copy incorrect addresses. Therefore, wallet providers give you the possibility to copy and paste addresses through separate buttons which are convenient and safe.

What is a Valid Crypto Address?

There are some signs to detect valid crypto addresses. 

Case sensitivity is one of the key attributes to recognize valid addresses. 

Depending on what kind of address you want to use, you can look for unique characteristics. We divide Bitcoin addresses into four types: Legacy, Script, SegWit and Taproot addresses. 

Legacy and Script addresses comprise 32 characters with case lettering starting with the prefix “1” or “3”. 

SegWit and Taproot address both don’t use case lettering. SegWit addresses contain 42 characters starting with the prefix “bc1q” and Taproot addresses contain 62 characters starting with the prefix “bc1p”. 

They all further omit characters like 0 (zero), O (capital o), l (lower L) and I (capital i). If you encounter a different string, it probably will be an invalid address. For Ethereum addresses, it is easier to recognize. 

These addresses always start with the prefix “0x” and comprise 42 characters in total. We can write them either with lower- or uppercase as they aren’t case sensitive. 

We write Ethereum addresses in hexadecimal notation, so A to F are the only letters you will find instead of the entire alphabet.

FAQ

Why Does My Ethereum Address Have Uppercase and Lowercase Letters?

Ethereum addresses are not case sensitive and can have both case lettering versions. 

The same address can contain both versions, which differs from Bitcoin. 

With Bitcoin, both versions could represent two separate addresses. In Ethereum, both versions always represent the same address. This allows for fewer mistakes and provides even the functionality to enable or disable checksums. 

With uppercase letters, you can perform a checksum which will check if the address is valid. With lowercase letters, this check won’t be performed.

Are Crypto Public Keys Case Sensitive?

Public keys are not case sensitive. 

Ethereum and Bitcoin both use the same principle to generate their respective public keys

Both store these keys in hexadecimal formats. Because of this, public keys are not case sensitive and can be written either in the upper- or lowercase lettering. From these addresses, the final wallet addresses are generated. 

In this wallet address creation step, both cryptocurrencies differ. Ethereum addresses remain in the hexadecimal format, but Bitcoin changes this format with Base58 or Bech32 encoding. 

Base58 uses case lettering and Bech32 remains without case lettering.

What Are Public Keys in Crypto?

Public keys are used to receive cryptocurrencies

They are derived from private keys. 

This process is part of the Public-Key-Encryption used by cryptocurrencies. Public keys aren’t directly used in transactions because they comprise long strings, which makes them not only bigger in data size but inconvenient, too. 

Therefore, they are further hashed into shorter versions, easier to use and smaller. These shorter versions are the public addresses the users actually use to process transactions.

Conclusion: Is a Crypto Address Case Sensitive?

capitalization matters in crypto addresses, as they can be case sensitive depending on their type. Bitcoin addresses have multiple types, with older ones being case sensitive.

To minimize errors, newer address formats were introduced that are not case sensitive. It is crucial to double-check addresses and use copy-paste or QR codes whenever possible to avoid the risk of mistyping and potential loss of funds.

Sources
About the Author:
Jordan Adams, with a rich background in Finance and Economics and specialized knowledge in blockchain, is a distinguished voice in the cryptocurrency community. Their journey in fintech and digital currency trading has equipped them to offer unique insights into digital finance. Jordan's writing demystifies cryptocurrency concepts with well-researched, practical advice. Engaged in the crypto community, Jordan shares timely market insights, fostering understanding of complex technologies and their practical applications in the evolving digital currency landscape.