
Time.is - ddw
http://time.is/
======
mwexler
I like Time.gov, personally; it was the first site I ever found around this
concept and so it has a soft spot.

I keep finding all my physical atomic clock synced clocks (yes, I have more
than one, they are cheap these days) disagreeing, sometimes by 2 seconds or
more, which makes me laugh (great ideas ruined by poor implementation). I find
many of the web sites (listed in comments or the original post) to also
differ, perhaps for similar reasons of implementation choices.

I would presume all the sites work off various implementations of NTP,
<http://www.ntp.org/> plus some trusted source.

I guess my question is: has anyone found a site which is really, really
accurate by reducing all the latency and lag, so what you see on the screen
really is, to whatever precision, accurate? And would said person have access
to a really good source for the comparison point? I don't seem to have one.
Yes, I should have stopped at 3 so that I could pick the 2 closest ones (like
the old saying: 1 clock is unsure, 2 clocks are worse, but 3 at least lets you
make a decision)

I wonder, would you need to have NTP on the client side synced to a trusted
source (say, in java, flash, or javascript) to get a good reading? Any server
serving over HTTP induces lag, I would think, and NTP is supposed to account
for transmission delays, or so I recall.

Thanks for sharing, another interesting time site to add to the collection.

~~~
ken
When I was a kid, my dad would always set our clocks by tuning the radio to
one of the atomic clock broadcasts from Fort Collins. This might be the same
source as your automatically synchronized clocks, but the advantage is that
it's human-listenable, and not going through any computer networks or
algorithms between Colorado and you.

[https://en.wikipedia.org/wiki/Radio_clock#List_of_radio_time...](https://en.wikipedia.org/wiki/Radio_clock#List_of_radio_time_signal_stations)

~~~
dfc
"The advantage is that it's human-listenable, and not going through any
computer networks or algorithms between Colorado and you." That is an
advantage?

The Fort Collins signal is awful in the northeast. If you want to deal with
the disadvantages of not using advanced computer algorithms to govern your
clock i would recommend the USNO's phone service:

Time Voice Announcer, Washington, DC: 202-762-1401 & 202-762-1069 (DSN
762-1401, 762-1069)

Time Voice Announcer, Colorado Springs, CO: 719-567-6742 (DSN 560-6742)

------
dfc
A lot of people are making disparaging comments about the acccuracy of the
site's time estimation with little or no explanation/data. All things
considered (three samples to estimate clock deltas and network delay) the time
estimation is fairly accurate.

time.is reports my clock is:

    
    
      -0.004 seconds (±0.021 seconds).
    

I have a stratum one time source on the local network (gps+pps) and my ntptime
agrees with the time.is estimation:

    
    
      dfc@bushido:~$ ntptime 
      ntp_gettime() returns code 0 (OK)
        time d3077752.4160a634  Sun, Mar 11 2012 15:11:14.255, (.255381196),
        maximum error 260579 us, estimated error 3294 us, TAI offset 34
      ntp_adjtime() returns code 0 (OK)
        modes 0x0 (),
        offset -4842.630 us, frequency 8.446 ppm, interval 1 s,
        maximum error 260579 us, estimated error 3294 us,
        status 0x6001 (PLL,NANO,MODE),
        time constant 10, precision 0.001 us, tolerance 500 ppm,
    
    

_NB: this is my laptop. so powersaving, heat fluctuations are adding a decent
amount of uncertainty from a metrological standpoint._

------
roryokane
I'm wondering how atomic clocks in general get set in the first place. Did, at
some point, scientists calculate when the sun was exactly overhead Greenwich
and call that noon? Because I would think that that calculation would have a
multi-second error, so setting your clock to the second would be pointless.

Or maybe there is no such thing as "actual physical time" and there is only
what people have agreed to call the standard. But in that case why do time
sources, such as time.gov and time.windows.com, still give different times? I
would think Microsoft would have fixed any bugs in their NTP implementation by
now, so it's not that. If it's just politics about nobody wanting to move to
someone else's time, then there's no way to tell which source is the real
standard, so your most practical choice is to synchronize your clock to the
times you deal with. That is, set your clock to your clock at work, or an
average of your friends clocks, or whatever source they get their time from. I
don't mind the existence of central time sources, because they are better than
having to go out and find someone else's clock, but they shouldn't call
themselves official if they aren't actually official.

So, does anybody know how the starting time for central time sources is
chosen, and if any source is worthy of being called "the real time"?

~~~
phillmv
Well… it's an arbitrary standard. We just call a day one full rotation of the
earth, and we just happen to divide it into 24hr periods with 60 subdivisions.

Theoretically, you could measure the rotation of the earth and call that a
day, but I have no idea how you would measure that down to the millisecond.

As to "Real Time", I don't know about the specific legalities, but the
standard goes as follows: everyone uses UTC
<http://en.wikipedia.org/wiki/Coordinated_Universal_Time> which is based off
the International Atomic Time
<http://en.wikipedia.org/wiki/International_Atomic_Time>

I too would be interested in how they picked the beginning epoch, i.e. "this
moment right here is midnight from which all other seconds shall be referenced
against" but in the grand scheme of things it doesn't matter - the only thing
that matters is the standard we agreed to measure against.

~~~
dfc
_"Theoretically, you could measure the rotation of the earth and call that a
day"_

This is not theoretical; this is known as sidereal time and is measured to the
nanosecond...

<http://en.wikipedia.org/wiki/Sidereal_time>

~~~
mceachen
Except that "…due to nutation, an actual sidereal day is not quite so
constant."

Yeah. Nutation.

Nutation "…is a rocking, swaying, or nodding motion in the axis of rotation of
a largely axially symmetric object, such as a gyroscope, planet, or bullet in
flight…"

<http://en.wikipedia.org/wiki/Nutation>

------
bbx
Exactly what I needed.

For the last few weeks, I've been trying to increase my productivity by
getting rid of time tracking. So I decided to hide my computer's clock.

Sometimes, like when I have an appointment, I still need to check what time it
is. Googling "time" doesn't always work (I don't know why exactly). So I
bookmarked this site [1] but the information density is so high that I need to
scan the page in order to get the time.

Time.is works quite well, with useful customization options, though it still
carries bits of useless information (like the time zones at the bottom). But
the time's font size is big enough to trigger instant focus.

UPDATE: as guptaneil pointed out, clicking the time (or navigating to
<http://time.is/just>) removes all the clutter. Thanks for the tip.

[1] <http://www.timeanddate.com/worldclock/city.html?n=328>

~~~
guptaneil
Accidentally found this, but tap the time to make the rest of the page fade
away. Or go to <http://time.is/just>

~~~
verelo
When i click on the time the google +1 button doesnt go away. Anyone else?

Firefox latest.

~~~
gibybo
Same here on Chrome. I would bet it's related to a unique feature of the
Google+ button: it shows your Google account info on hover.

------
mtr
Shows incorrect time for Chile. DST isn't until April 28th.
[http://www.timeanddate.com/news/time/chile-longer-
dst-2012.h...](http://www.timeanddate.com/news/time/chile-longer-
dst-2012.html)

~~~
apaprocki
It means that they didn't apply the latest tzdata2012a or b update released
the first week of March which contained the America/Santiago zone change.

~~~
phillmv
Time is a surprisingly difficult subject to get right.

~~~
apaprocki
Governments are free to change timezone rules at will with no real advance
notice. Case-in-point, tzdata2012b was just published a few days ago and
already on the tz mailing list Morocco's DST date is changing and Haiti
apparently changed as well.

The problem is exacerbated by the fact that most systems rely on OS tzdata
instead of shipping it themselves, yet in many places the administration of
the OS is separated / walled off from the devs who maintain the apps which
actually suffer from the bugs.

I feel bad for users who live in countries whose governments play with DST law
on a whim, because they are certainly destined to encounter bugs throughout
the Internet because it isn't always reasonable to ask all administrators
around the globe to patch all production systems in a matter of a few days.

------
aeden
Nice job on this. I usually use <http://everytimezone.com> but I like how I
can configure this with the zones that matter to me. It would be nice if I
could easily use my favorites when doing the Here -> There comparison.

------
libria
OP, what does this line do?

    
    
        if (wn == 1) pwn = '1-ին շաբաթ';
    

It looked like something related to week number; looks interesting.

~~~
Aramgutang
In a fuller context:

    
    
        if(p_wn=='hy'){if(wn==1)pwn='1-ին շաբաթ';else pwn=wn+'-րդ շաբաթ'}
    

So if the locale is "hy" (Armenian), and the week number is one, set the
string to "1st week", else set the string to "#th week" (both in Armenian).

Unlike English, which also has exceptions for "2nd" and "3rd", Armenian only
uses a different suffix for "1st".

------
mrud
I really like <http://worldtimebuddy.com/> as it allows you to see time zone
differences without the need to calculate it yourself.

~~~
djsla
It does not do clock sync/accuracy determination. _Time.is_ is rather unique
that way. However, I'm skeptical over the importance of that feature.

disclosure: worldtimebuddy founder.

------
guylhem
I like it a lot. Easy to remember URL. However the services offered are not so
good.

At least there is no RFC 867 and RFC 868 date on port 37 and port 13.

This is deprecated, I know, but rdate is still the easiest way to fix the date
on a system which do not require precision. I did run my own minimal daemon on
my DSL modem for the various gizmos I have that include busybox (thus rdate)
and where recompiling to get a ntp would be overkill. (the right day and the
right hour are more than enough)

time.nist.gov removed RFC 867 (port 13) and 868 (port 27) support. time-
nw.nist.gov kept it a bit longer, then I used by DSL modem, which went in RMA
and so guylhem.org is also down.

I'll try to email the author and offer to give a hand.

~~~
dfc
rdate is awful that is why NIST killed it. If you want a fire and forget time
check:

    
    
      sntp pool.ntp.org

~~~
guylhem
I know rdate is awful but when that's all you have and don't feel like
crosscompiling for a device which does not even requires a minute of
precision, it does the job.

Technical excellence is not always required, and having more choices usually
is a good idea.

------
riobard
I still like this one instead: <http://everytimezone.com/>

------
moe
Reminds me of the radio clock that I have in the bathroom.

It is labeled "DCF signal - precision time", yet is off by hours most of the
time (jumps randomly).

I keep it for the entertainment value. Guests always have a good chuckle when
they enter the bathroom at 16:41 and leave it at 23:41.

------
hrktb
The handling of internationalization is surprisingly good. Texts, including
town names, are almost all shown in the preferred language, and the size
variations introduced by the translations are well handled.

------
zarroba
I would still prefer to have the option to select the timezone. Sometimes I
want to attend some workshops that announce the time in one of the US
timezones and its always difficult to do the conversion.

~~~
napoleoncomplex
What would be ideal in this case is a browser add-on or a bookmarklet that
enables dynamic conversion.

The add-on would be simpler, as a text-select and right click could show the
selected time in your own time zone in the right-click menu.

It's something I've missed every single time some press conference or event is
announced, and it just says 12:00 EST.

------
gwern

        Your clock is 0.2 seconds slow.
        Accuracy of synchronization was ±0.625 seconds
    

If the result is within the margin of error, wouldn't it be better to just not
tell me at all?

~~~
dfc
I imagine that the author of the page has some scientific background and
therefore feels that it is appropriate to publish the margin of error
alongside any estimation.

------
7952
It would be good if you could make the title of the tab show the time.

------
tibbon
Simple, but awesome. About two years ago I had the idea (but never
implemented) to try and re-make various since use web tools and calculators
using modern web technology. Things like interest/mortgage calculators,
voltage drop calculators, difference between two dates, etc.

So many of them like Time.gov rely on stuff like Flash or Java, or 1998 style
Javascript, which I don't really dig. Definitely a nice little hole there for
making something cool.

------
acerimmer
Another very nice web for timezones is <http://tmzns.com>.

------
ideaoverload
The clock display is nice but not a killer for me. Here&There time comparison
in different time zones is the best I have seen. Full page calendar with
multiple months is very simple but works great for me. This is becomes my
favorite site for time/date related stuff.

------
cynwoody
Very nice!

My little Ubuntu machine is -0.018 seconds (±0.009 seconds).

My MBP is -0.012 seconds (±0.021 seconds).

I recommend you add a percentile score of exactness, along with breakdowns
based on platform, and suggestions about what to do if the percentile is
disappointing.

------
iag
I am seeing roughly +/- 0.1s accuracy range on my browser. Can someone please
enlighten me on why we cannot reduce this further? I assume this page has
<100ms response time, can't they get to a better accuracy range?

------
Steveism
I've always been fond of the official navy.mil time site. It's an ascii lovers
paradise: <http://tycho.usno.navy.mil/cgi-bin/timer.pl>

------
drewjoh
Reminded me of this (Daylight Savings Time explained):
<http://www.youtube.com/watch?v=84aWtseb2-4> Madness!

------
chanux
Simple and amazing.

I used a simple shell script to query timezone info to find world time in CLI
<https://gist.github.com/2020097>

------
ilaksh
Wow.. that's a new one. Now I have to buy an .is domain.

~~~
TazeTSchnitzel
what.is? love.is? it.is?

------
MattRogish
Cool site! QR code on the "About" page is a head-scratcher, though..
<http://time.is/about>

~~~
jarek
The idea is you can scan it with your phone and not have to type the URL in.
Not sure how many people actually do that though.

~~~
MattRogish
A) If you're viewing on your phone, it's mobile optimized B) If you're viewing
it on your desktop, why would you want to go to your phone? C) Time.is has to
be the _easiest_ URL to enter by hand in a device browser. :D

~~~
jarek
I'm not saying it's very useful, but if you see it on your desktop and want to
check it or save it on your phone (to verify the time on your phone/QR-and-
web-enabled mobile device, to bookmark it for future reference when on the go,
etc), the code might help. I've seen this used better than just on an 'about'
page, though.

------
mdda
For those alarmed at the offset...

# yum install ntpdate

# ntpdate -u ntp-1.vt.edu

# hwclock -w

"Your time is exact!"

~~~
dfc
ntpdate is dead and is discontinued. Use an actual daemon to govern your time
source.

I thought redhat installed ntpd or chrony by default. I know chrony is the
default for the next fedora release. If you have ntpd/chronyd installed your
advice is horrible and not just because you pointed everyone to Virginia
Tech's time server.

~~~
mdda
Thanks : Updated procedure (for Fedora without chronyd/ntpd running already) :

# yum install chrony

# systemctl enable chronyd.service

# systemctl start chronyd.service

Sorry if the (working) pointers before were horrible. Hopefully this is more
useful - the servers used are {N}.fedora.pool.ntp.org.

~~~
dfc
chronyd is a lot more mindful of battery/power considerations than ntpd. It is
an interesting approach to endpoint time synchronization compared to the ntp
reference implementation.

------
treelovinhippie
Any idea what geolocation method they're using here? It got my city spot-on
when usual IP geolocators put me elsewhere.

------
aravindc
This is exactly what I wanted. I used to google everytime to find time. Not
anymore, and it looks cool too.

~~~
wilfra
Same, Google just lost a few searches a week from me :)

------
ynniv
When clicking the time in FF 10.0.2, everything disappears expect the Google
+1.

------
sylvinus
Nice, however on my Chrome Mac there's a flash each second with the re-render.

------
samt
Tell me I'm not the first to see the irony of a page full of comments debating
ntp, GPS and atomic clocks, while there are two interesting front page stories
about the value of ambitious goals.

------
pbhjpbhj
that reminds me - todo: <http://whatsthetime.in/>

------
silentscope
clever url folks.

~~~
silentscope
I wasn't being sarcastic guys. I meant that, it's pretty clever.

~~~
eropple
You weren't downvoted for being sarcastic.

You were downvoted for adding nothing to the discussion.

------
Shtirlic
White on black is perfect.

~~~
Tobu
I'd prefer the logo to be a bit more subdued over the relaxing black
background.

------
sabatier
This is gorgeous.

