why are the speed conversions on the speed test inaccurate?

[onamae]

For example here is my score that I get with the download test.

6895 Kbps or 6.9 Mbps (842 kB/s)

But when I use googles built in calculator I get different results...? whos right, whos wrong!!??

in google when I type"6895 Kbps to Mbps" I get 6895 Kbps = 6.73339844 Mbps but this site says 6895 equals 6.9... thats a large variance!

in google "6895 Kbps to kB/s" gives me 6895 Kbps = 861.87500 kB/s not the 824kB/s that this site says is the correct conversion... so whats the deal, am I missing something?

any help appreciated thanks 

[php]

Welcome to the forum

This really depends who you talk to and how you calculate the conversions.  Many of the conversions are rounded, hence the variance.  For example, a common way to convert Kbps to kB/s is to divide by 8.192.  Then 6895Kbps would be 841.67kB/s.  Google apparently converts Kbps to Mbps by dividing by 1024, another common conversion.

See here and here for more info.

php

(I think this post made sense, but I'm falling asleep so it's hard to tell )

[onamae]

so basically the conversion on this site is completely wrong thats really odd... why dont they fix it and make it accurate, why would you guys round off numbers when its just as easy to be exact.... which is kinda important for a calculator, if it rounds off numbers it isn't a calculator period, more like an educated guess.  This makes me doubt the accuracy of the speed test itself, not a good appearance for a site that rates your bandwidth.

made up math forumulas gets you the wrong answer, who would have thought

[tommie gorman]

Welcome to the forum onamae.

So who said that Google was right?

[VanBuren]

so basically the conversion on this site is completely wrong thats really odd... why dont they fix it and make it accurate, why would you guys round off numbers when its just as easy to be exact.... which is kinda important for a calculator, if it rounds off numbers it isn't a calculator period, more like an educated guess.  This makes me doubt the accuracy of the speed test itself, not a good appearance for a site that rates your bandwidth.

made up math forumulas gets you the wrong answer, who would have thought

dude i suggest you relax and read, testmy.net calculator is the most accurate you will get

quote from http://lyberty.com/encyc/articles/kb_kilobytes.html

The International Electrotechnical Commission (IEC) attempted to deal with the confusion in 1998/1999 by recommending a new set of "binary prefixes". They sought to distinguish between the standard SI prefixes (base 10) and computing prefixes (base 2) by assigning "KiB", "MiB" (kibibyte, mibibyte), on so on to computing prefixes (for example, "one kibibyte (1 KiB) equals 1024 Bytes").... But 6 years later, these terms have had very limited adoption. It appears they have so far lost their battle to retain the original meaning of K /M /G...

1  MegaByte =1 024  KiloBytes,  1  KiloByte =1 024 Bytes

The main problem with the "Kibi-"/"Mebi-" approach recommended by the IEC is the widespread use of computer operating systems (especially Microsoft Windows) that have effectively standardized "KB" (KiloByte) as 1,024 Bytes, "MB" (MegaByte) as 1,024 KB ( 1,048,576 Bytes), and "GB" (GigaByte) as 1,024 MB.

Millions of people use these abbreviations in their daily use of computers; many more than the number of people who use the "proper SI meanings" -- and even people who refer to things like "kilometers" or "kilograms" know perfectly well that a "Kilobyte" is 1,024 Bytes, not 1,000 Bytes.

The practical upshot of this is that, unless you can get Microsoft to start using the "KiB" abbreviation throughout their interfaces and documentation, then get millions of programmers to follow suit, we have to accept that "KB", "MB", et cetera, is taken, and work from there. (Face it: Microsoft trumps the IEC. I know these statements annoy Linux users, but Linux has also traditionally used the same definitions.)

Furthermore, another large problem with their approach was to introduce ambiguity by attempting to redefine established abbreviations, and introduce new abbreviations for established refences, instead of introducing new abbreviations for the less frequently used definitions. This means that anyone reading historical documentation or using any program now has to wonder "does this use of MB indicate the older use of MB (1,024 KB), or does it mean the IEC definition of MB (1,000 KB)??"

Arguably, an alternate approach would make more sense: let KB, MB, and GB remain as multiples of 1,024, but refer to DATA TRANSFER always in terms of bits; kbps, mbps, gbps, tbps, and so on:

    kbps (kilobits/sec) means thousands of bits per second

    mbps (megabits/sec) means millions of bits per second

    gbps (gigabits/sec)means billions of bits per second

    tbps (terabits/sec) means trillions of bits per second (as in "terabit router" or "terabit speeds")

    pbps (petabits/sec) means quadrillions of bits per second.

Examples:

    * "Gigabit Ethernet [1000Base-T] is capabile of speeds up to 1000 mbps (mega-bits per second), or 1 gbps."

    * "10Base-T ethernet operates at 10 mbps and uses baseband transmission methods."

    * "SATA II defines the architecture (SATA-300) for Serial ATA communications of up to 3 gbps."

also check this thread http://www.testmy.net/forum/index.php?topic=10714.msg105309#msg105309

if you came here to bash testmy.net and the accuracy of the speed test itself, good luck !

VanBuren

by the way welcome to the site 

[tommie gorman]

so basically the conversion on this site is completely wrong thats really odd... why dont they fix it and make it accurate, why would you guys round off numbers when its just as easy to be exact.... which is kinda important for a calculator, if it rounds off numbers it isn't a calculator period, more like an educated guess.  This makes me doubt the accuracy of the speed test itself, not a good appearance for a site that rates your bandwidth.

made up math forumulas gets you the wrong answer, who would have thought

Google is not GOD. It is like a computer, it is only as accurate as the operator's info!

[FiosFiend]

Just because Google rounds differently then testmy doesn't mean they're right.

Perhaps they should adopt the testmy approach!

[onamae]

I would like to prove that the calculator is wrong so here goes just read and you will see!

First off the conversion chart and the calculator on this very same site contradict each other.

The conversion chart, which is correct by the way http://www.testmy.net/tools/conversion_table.php states that 1024 Bytes equals 8192 bits which is correct cause 8 bits equals 1 byte, its a fact plain and simple no gray area.

Now go ahead and try to convert 1024 KiloBytes into Kilobits http://www.testmy.net/tools/convert.php?gen=gen&num=1024&MAKE=CONVERT+%21T&c=0 and low and behold the wrong answer! it gives you 8389 instead of the correct answer 8192.

To further prove the calculator is clearly wrong lets try this in the calculator, now remeber 8 bits equals 1 Byte...

Lets convert 1Kilobyte to Kilobits http://www.testmy.net/tools/convert.php?gen=gen&num=1&MAKE=CONVERT+%21T&c=0

aha it correctly states 8 Kilobits...

OK now lets try 2Kilobytes to Kilobits http://www.testmy.net/tools/convert.php?gen=gen&num=2&MAKE=CONVERT+%21T&c=0

and again its states the correct answer 16 Kilobits...

But here is where it goes off, lets try 3Kilobytes to Kilobits which should give us 24 since 3x8 is 24...

http://www.testmy.net/tools/convert.php?gen=gen&num=3&MAKE=CONVERT+%21T&c=0

But alas we get 25 as the answer! From here on the larger the amount of data you convert the wider the variance gets!

So there you see the calculator is plain out wrong and should be fixed, I love the site I think its great, I didn't mean to piss off people but just wanted to state that there is a problem with the calculator and hopefully it can be fixed to make a great site even better 

[CA3LE]

You are correct... there was actually a "1000" where "1024" should have been -- it's been resolved

to error is human I guess

[CA3LE]

thanks for bringing that to my attention by the way

[brock01]

i like it when someone can take the "blame" for a human mistake, shows how much of a man he is

CA3LE ftw:)

good man, making the site better one step at a time

[CA3LE]

i like it when someone can take the "blame" for a human mistake, shows how much of a man he is

CA3LE ftw:)

good man, making the site better one step at a time

ty

http://www.testmy.net/tools/convert.php?gen=gen&num=1000&c=0

all fixed

[CA3LE]

actually google is wrong about something.... this may be a first, lol

they think that Mbps to Kbps conversion is 1024 --- it's actually 1000

http://www.google.com/search?hl=en&q=1+Mbps+to+Kbps

http://www.google.com/search?hl=en&lr=&q=1000+Kbps+to+Mbps

They are FLAT OUT WRONG!  -- I did however have a minor calculation that was wrong, further investigation reveiled that a number was being put into the equasion that had already been rounded... this has been fixed

WOW, Google was WRONG........ really, they were REALLY wrong?!?!?!?!  haha

[tommie gorman]

Google is not GOD. It is like a computer, it is only as accurate as the operator's info!

actually google is wrong about something.... this may be a first, lol

they think that Mbps to Kbps conversion is 1024 --- it's actually 1000

http://www.google.com/search?hl=en&q=1+Mbps+to+Kbps

http://www.google.com/search?hl=en&lr=&q=1000+Kbps+to+Mbps

They are FLAT OUT WRONG! -- I did however have a minor calculation that was wrong, further investigation reveiled that a number was being put into the equasion that had already been rounded... this has been fixed

WOW, Google was WRONG........ really, they were REALLY wrong?!?!?!?!  haha

I got one right.  :haha: :haha: :haha:  CA3LE

[CA3LE]

I got one right.  :haha: :haha: :haha: CA3LE

yes you did.. haha  -- that shit is funny, I thought google knew everything!!  I checked with like 10 resources, and I'm correct. 

[VanBuren]

For example here is my score that I get with the download test.

6895 Kbps or 6.9 Mbps (842 kB/s)

But when I use googles built in calculator I get different results...? whos right, whos wrong!!??

google indeed

converting Transferspeeds always in terms of bits Mbps, Gbps, Kbps you should divide it in 1000 and not 1024 as my quote in previous post said

Arguably, an alternate approach would make more sense: let KB, MB, and GB remain as multiples of 1,024, but refer to DATA TRANSFER always in terms of bits; Kbps, Mbps, Gbps, tbps, and so on:

    Kbps (kilobits/sec) means thousands of bits per second

    Mbps (megabits/sec) means millions of bits per second

    Gbps (gigabits/sec)means billions of bits per second

    tbps (terabits/sec) means trillions of bits per second (as in "terabit router" or "terabit speeds")

    pbps (petabits/sec) means quadrillions of bits per second

im glad you found a problem in our convert tool, and Cable got it fixed 

no hard feelings here, you was both right and wrong since you didnt see the problem in googletool and so was i since i couldnt find the problem in conversion tool

This is what makes this site get better, feedback and suggestions to change things from members

im also glad your intention wasnt to piss of ppl 

again welcome to the site

VanBuren