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Word #240 00011101111

bulb

/bʌlb/

Binary Representation

0
0
0
1
1
1
0
1
1
1
1

11-bit index: 00011101111 (decimal 239)

Position

#240 of 2048

Hex Index

0x0EF

4-Letter Prefix

bulb

About "bulb" in BIP39

"bulb" is the #240 word in the official BIP39 English mnemonic wordlist. It is encoded as the 11-bit binary value 00011101111 (decimal index 239), placing it at the 12% mark of the full 2048-word list.

The 4-letter prefix "bulb" uniquely identifies this word among all 2048 entries. At just 4 characters, "bulb" is one of the shorter words in the BIP39 list, making it quicker to type during wallet recovery but potentially easier to confuse with similar short entries.

Positioned in the first quarter of the wordlist (index 239), "bulb" starts with "B" — a letter group containing 117 words total. It is word #104 within that group. Words early in the list have lower binary values with more leading zeros, which can be relevant when analyzing raw entropy data.

In a 12-word seed phrase, each word encodes 11 bits of entropy. The probability of "bulb" appearing in any specific position of a randomly generated phrase is 1 in 2048 (≈ 0.049%). A complete 24-word phrase encodes 256 bits of entropy, providing security equivalent to a key space of approximately 1.16 × 10⁷⁷ — far beyond the reach of brute-force attacks.

Word #240 in the Other 9 BIP39 Wordlists

Every official BIP39 wordlist has exactly 2048 entries, so index 239 encodes the same 11-bit value (00011101111) in every language. A wallet configured for one of these languages would use this word instead of "bulb":

Czech dnes
French biotype
Italian bisesto
Japanese えんぜつ
Korean 글자
Portuguese baiano
Spanish besar
Chinese (Traditional)
Chinese (Simplified)

Similar Words — Check Carefully During Recovery

One BIP39 word differs from "bulb" by just a single letter — the most common source of typos when a seed phrase is entered by hand:

Words sharing the first three letters "bul":

Reminder: the first 4 letters of every BIP39 word are unique across the whole list, so "bulb" always identifies "bulb".

More BIP39 Words Starting with "B"

View all words starting with "B"