1 XBT = 1 BTC = 1
BTCI wonder who else is still using XBT symbol for bitcoin. This is Xe Currency Conversion App, I'm using most of the time and noticed they still use XBT and yes bitcoin is the only crypto currency it supports.
If you don't know XBT is also a symbol for Bitcoin and as per ISO standard 4217 currency code for Bitcoin is XBT.
However BTC is most widely used but it violates ISO 4217 because it begins with BT which is the reserved country code for Bhutan. (Bhutan's currency is Ngultrum and full currency code is BTN)
Bitmex exchange is still using XBT and Kraken exchange has been using XTB symbol for Bitcoin but they switched to BTC as of
April 26th, 2021 but in their APIs they still use XBT.
The abbreviation "XBT" comes from the International Standards Organization (ISO) that maintains a list of internationally recognized currencies. The standard dictates that if a currency is not associated with a particular country, it should begin with an “X”, hence "XBT". Another example of this is the abbreviation for gold, "XAU".
Interesting to note ISO symbols for some precious metals are:
XAU Gold
XAG Silver
XPD Palladium
XPT Platinum
While following the above rule don't forget
not all that glitters is gold bitcoin.
XRP Ripple
XLM Stellar
XMR Monero
I personally like BTC but based on "precious metals" theory XBT isn't bad either.