Satoshi / BTC Unit Converter

Bitcoin amounts show up in four different notations depending on where you’re reading them. A node’s RPC output quotes Satoshi, the integer base unit. A Lightning invoice often uses bits (μBTC). A point-of-sale receipt might round to mBTC. A wallet balance is almost always BTC. None of those four numbers look related on sight, and converting one by hand means moving a decimal point 2, 5 or 8 places without a mistake.

This tool does that shift with BigInt arithmetic rather than floating-point, so a value quoted down to the exact satoshi never drifts the way a JavaScript Number can once it exceeds about 15 significant digits. Type a value in any of the four units and the other three update immediately.

Worked Example: Converting Bitcoin’s Dust Limit

Click Load Sample and the input fills with 100000000 in the Satoshi tab, which the results grid shows as exactly 1 BTC, 1000 mBTC and 1000000 bits. Click Load Sample again and it switches to Bitcoin’s real dust limit, 546 satoshis: the smallest standard P2PKH output most nodes will relay, shown here as 0.00000546 BTC. Switching the active unit tab keeps the same real-world amount, not the same raw number; typing 1 in Satoshi and clicking the BTC tab shows 0.00000001, the actual value carried forward.

How the Conversion Method Works

Every unit’s scale is defined relative to Satoshi, so the input is parsed into a raw satoshi count once, regardless of which unit it was typed in, then reformatted for each of the other three: divide by the unit’s satoshi scale, keep the integer part as the whole number, and turn the remainder into a trimmed decimal tail. Bit is 10² satoshis, mBTC is 10⁵, and BTC is 10⁸; all of it runs on BigInt, so there is no rounding step to get wrong for values this shift alone can produce.

Accuracy Limits: What This Tool Doesn’t Enforce

• Typing digits after the satoshi place in Satoshi mode is silently truncated, since there is no smaller real Bitcoin denomination to represent it. In BTC mode, a 9th decimal digit is truncated the same way.
• The converter does not enforce Bitcoin’s 21,000,000 BTC hard supply cap. Entering a larger figure still converts correctly; it just describes an amount the protocol will never actually mint.
• An unparseable value, such as two decimal points, produces “Enter a value using only digits and a single decimal point.” rather than a silently wrong number.
• There is no price feed here by design. This tool converts between Bitcoin’s own denominations only; it has no opinion on what any of them are worth in fiat.