Can someone tell me what does the hex value mean?

[hailong94]

Hello all,
I wonder if someone could tell me what does this hex '#2314b545' in '/data/flights/vn18#2314b545' possibly mean?

[OFBleeker]

Hi
'Hex' is short for 'hexadecimal' or 'base 16'. In ordinary 'decimal' counting, we count from 0-9 until we reach 10. Reaching '10' means we have had 10 to the power of 1 (=10) plus 0.
Example: Two hundred and fifteen (215) stands for 2*10^2 (=200) plus 1*10^1 (=10) plus 5*10^0 (=5)
Similarly, hexadecimal counts to 15 before adding the next digit, thus denoting powers of 16 in stead of powers of 10 in decimal, or in stead of powers of 2 in binary. Etc.
It allows for a much wider range of numbers. However, since we only "know" 10 (decimal) figures (because we have all been accustomed to decimal expressions), hex uses up to '9' as in decimal and then continues on with alpha-characters, until reaching the count of F (=15(dec)); then after that the first power of 16 which would be 10(hex)).
As a result: '10' in decimal would be A in hex. Likewise, 15(dec)=F(hex); 16(dec)=10(hex) and it is why numbers expressed in hex show figures and characters.

[hailong94]

Hi OFBleeker, what i mean is how do one calculate this hex value. Because i want to manually construct the url with the hex value rather than clicking on the page, but i dont know what is this hex is based on.

[OFBleeker]

Hi--
The [hex] code of an aircraft is assigned; it is an ICAO value contained in the 24 bit address of a transponder. The number is "tied" to the aircraft by way of registration. So once that has been done it is no longer subject to calculation. The value is issued by the aircraft transponder in its reply upon interrogation, or when it broadcasts [unsolicited] squitters as in ADS-B, so that the one receiving this information can decide from which aircraft it has come. Hope this helps...

[hailong94]

Thanks! Very much appreciated.

[hailong94]

Hi OFBleeker,
I think the hex value on the url is not ICAO value. It is a 8 digits hex value while a 24 bit address corresponds to just 6 digits hex value.

[Oblivian]

Its an ID of the currently tracked aircraft that FR24 have assigned to each target.

[hailong94]

Hi oblivian, is there a way to get this id in programming code? Or calculate it in code, something like that. I would like to construct the url from code but all i have is the flight number so i still have to click on either playback or live to track the flight. I would like to skip this clicking part. Thanks alot.

[Oblivian]

No, And doing so would likely breach their terms of use.

It's automatic. And exclusive to the server. Generated when you use search etc. It will auto add when using callsign URL. EG https://www.flightradar24.com/FJI811

[hailong94]

Thanks for your reply!