How to Convert Hexadecimal to Octal
Enter an integer using 0 through 9 and A through F. The converter reads it in base 16 and writes the same value in base 8. Copy the output or reverse the direction to verify it. Whitespace grouping does not change the value.
How Hexadecimal and Octal Represent Values
In hex, each place is a power of 16; in octal, each place is a power of 8. Starting at the right, multiply each digit by its place value and add the results. Conversion changes notation, not magnitude.
Hexadecimal to Octal Conversion Examples
For example, 2A in hex equals 52 in octal, and both equal decimal 42. Work through the positional sum on a small example before converting a long identifier. Leading zeros affect display width but not the integer value.
Common Uses and Edge Cases
The tool accepts signed integers and uses exact integer arithmetic. It does not interpret a negative value as a fixed-width two’s-complement bit pattern. Fractions and scientific notation are not supported. Use the text translators for encoded bytes rather than treating a whole message as one number.
More examples and technical details
How to Convert Hexadecimal to Octal
Converting hexadecimal to octal by hand is straightforward once you know the routine. The converter above does it instantly, but working through the steps yourself is the fastest way to understand what is actually happening to the digits.
- Convert each hexadecimal digit into its 4 digit binary form.
- Join all the bits together into one binary string.
- Regroup that binary string into blocks of 3, working from the right and padding the left with zeros.
- Convert each block into a single octal digit.
Worked example: 1F4
Result: (1F4)¹⁶ = (764)⁸
The Hexadecimal System
Hexadecimal is the base 16 system. It uses the digits 0 through 9 and then the letters A through F to stand for the values 10 through 15. Its key property is that one hex digit represents exactly four binary digits, a nibble, so a single byte is always two hex characters. That compactness is why hex shows up everywhere in computing: HTML colour codes such as FFFFFF for white and 000000 for black, memory addresses, MAC addresses, hash digests, and byte level debugging output.
Hexadecimal uses the digits 0 through 9 and A through F.
The Octal System
Octal is the base 8 numeral system and uses the digits 0 through 7. Its usefulness comes from the fact that one octal digit maps exactly onto three binary digits, so it is a compact way to write binary without doing real arithmetic. Octal was common on early minicomputers with 12, 24, and 36 bit words. Today the place most developers still meet it is Unix file permissions, where a command such as chmod 755 sets read, write, and execute bits three at a time.
Octal uses the digits 0 through 7.
Hexadecimal to Octal Conversion Examples
Hexadecimal to Octal Conversion Chart
A full reference table for the values 1 to 256. Use it to check a conversion quickly or to look up a common value without typing anything.
| Hexadecimal | Octal |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 4 |
| 5 | 5 |
| 6 | 6 |
| 7 | 7 |
| 8 | 10 |
| 9 | 11 |
| A | 12 |
| B | 13 |
| C | 14 |
| D | 15 |
| E | 16 |
| F | 17 |
| 10 | 20 |
| 11 | 21 |
| 12 | 22 |
| 13 | 23 |
| 14 | 24 |
| 15 | 25 |
| 16 | 26 |
| 17 | 27 |
| 18 | 30 |
| 19 | 31 |
| 1A | 32 |
| 1B | 33 |
| 1C | 34 |
| 1D | 35 |
| 1E | 36 |
| 1F | 37 |
| 20 | 40 |
| 21 | 41 |
| 22 | 42 |
| 23 | 43 |
| 24 | 44 |
| 25 | 45 |
| 26 | 46 |
| 27 | 47 |
| 28 | 50 |
| 29 | 51 |
| 2A | 52 |
| 2B | 53 |
| 2C | 54 |
| 2D | 55 |
| 2E | 56 |
| 2F | 57 |
| 30 | 60 |
| 31 | 61 |
| 32 | 62 |
| 33 | 63 |
| 34 | 64 |
| 35 | 65 |
| 36 | 66 |
| 37 | 67 |
| 38 | 70 |
| 39 | 71 |
| 3A | 72 |
| 3B | 73 |
| 3C | 74 |
| 3D | 75 |
| 3E | 76 |
| 3F | 77 |
| 40 | 100 |
| Hexadecimal | Octal |
|---|---|
| 41 | 101 |
| 42 | 102 |
| 43 | 103 |
| 44 | 104 |
| 45 | 105 |
| 46 | 106 |
| 47 | 107 |
| 48 | 110 |
| 49 | 111 |
| 4A | 112 |
| 4B | 113 |
| 4C | 114 |
| 4D | 115 |
| 4E | 116 |
| 4F | 117 |
| 50 | 120 |
| 51 | 121 |
| 52 | 122 |
| 53 | 123 |
| 54 | 124 |
| 55 | 125 |
| 56 | 126 |
| 57 | 127 |
| 58 | 130 |
| 59 | 131 |
| 5A | 132 |
| 5B | 133 |
| 5C | 134 |
| 5D | 135 |
| 5E | 136 |
| 5F | 137 |
| 60 | 140 |
| 61 | 141 |
| 62 | 142 |
| 63 | 143 |
| 64 | 144 |
| 65 | 145 |
| 66 | 146 |
| 67 | 147 |
| 68 | 150 |
| 69 | 151 |
| 6A | 152 |
| 6B | 153 |
| 6C | 154 |
| 6D | 155 |
| 6E | 156 |
| 6F | 157 |
| 70 | 160 |
| 71 | 161 |
| 72 | 162 |
| 73 | 163 |
| 74 | 164 |
| 75 | 165 |
| 76 | 166 |
| 77 | 167 |
| 78 | 170 |
| 79 | 171 |
| 7A | 172 |
| 7B | 173 |
| 7C | 174 |
| 7D | 175 |
| 7E | 176 |
| 7F | 177 |
| 80 | 200 |
| Hexadecimal | Octal |
|---|---|
| 81 | 201 |
| 82 | 202 |
| 83 | 203 |
| 84 | 204 |
| 85 | 205 |
| 86 | 206 |
| 87 | 207 |
| 88 | 210 |
| 89 | 211 |
| 8A | 212 |
| 8B | 213 |
| 8C | 214 |
| 8D | 215 |
| 8E | 216 |
| 8F | 217 |
| 90 | 220 |
| 91 | 221 |
| 92 | 222 |
| 93 | 223 |
| 94 | 224 |
| 95 | 225 |
| 96 | 226 |
| 97 | 227 |
| 98 | 230 |
| 99 | 231 |
| 9A | 232 |
| 9B | 233 |
| 9C | 234 |
| 9D | 235 |
| 9E | 236 |
| 9F | 237 |
| A0 | 240 |
| A1 | 241 |
| A2 | 242 |
| A3 | 243 |
| A4 | 244 |
| A5 | 245 |
| A6 | 246 |
| A7 | 247 |
| A8 | 250 |
| A9 | 251 |
| AA | 252 |
| AB | 253 |
| AC | 254 |
| AD | 255 |
| AE | 256 |
| AF | 257 |
| B0 | 260 |
| B1 | 261 |
| B2 | 262 |
| B3 | 263 |
| B4 | 264 |
| B5 | 265 |
| B6 | 266 |
| B7 | 267 |
| B8 | 270 |
| B9 | 271 |
| BA | 272 |
| BB | 273 |
| BC | 274 |
| BD | 275 |
| BE | 276 |
| BF | 277 |
| C0 | 300 |
| Hexadecimal | Octal |
|---|---|
| C1 | 301 |
| C2 | 302 |
| C3 | 303 |
| C4 | 304 |
| C5 | 305 |
| C6 | 306 |
| C7 | 307 |
| C8 | 310 |
| C9 | 311 |
| CA | 312 |
| CB | 313 |
| CC | 314 |
| CD | 315 |
| CE | 316 |
| CF | 317 |
| D0 | 320 |
| D1 | 321 |
| D2 | 322 |
| D3 | 323 |
| D4 | 324 |
| D5 | 325 |
| D6 | 326 |
| D7 | 327 |
| D8 | 330 |
| D9 | 331 |
| DA | 332 |
| DB | 333 |
| DC | 334 |
| DD | 335 |
| DE | 336 |
| DF | 337 |
| E0 | 340 |
| E1 | 341 |
| E2 | 342 |
| E3 | 343 |
| E4 | 344 |
| E5 | 345 |
| E6 | 346 |
| E7 | 347 |
| E8 | 350 |
| E9 | 351 |
| EA | 352 |
| EB | 353 |
| EC | 354 |
| ED | 355 |
| EE | 356 |
| EF | 357 |
| F0 | 360 |
| F1 | 361 |
| F2 | 362 |
| F3 | 363 |
| F4 | 364 |
| F5 | 365 |
| F6 | 366 |
| F7 | 367 |
| F8 | 370 |
| F9 | 371 |
| FA | 372 |
| FB | 373 |
| FC | 374 |
| FD | 375 |
| FE | 376 |
| FF | 377 |
| 100 | 400 |
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Frequently asked questions
How do I convert hexadecimal to octal?
Read the input as base 16 and express its value in base 8; enter it here for an automatic result.
Can this converter handle negative or large values?
Yes. Signed and large integers use exact BigInt arithmetic, subject to practical browser resource limits. Fractions are not supported.
How can I verify the octal result?
Convert octal back to hex and compare the numeric value; leading zeros may be normalized.
Is the conversion processed in my browser?
Yes. No number is sent to a conversion server.