American - Long Island, NY
kill-AH-meh-ter
Same place we get the “ah” sound in the words cot, tot, rottweiler - the short “O” and “ah” sounds are virtually interchangeable in English as most Americans speak it.
As for me it’s “kil AH meh ter” as well.
Milwaukee, Wisconsin. Grew up in Madison, Wisconsin.
My entire life it’s been pronounced kil - AH - meh - ter.
Currently live in West Texas, but have lived in North Carolina, Indiana, Germany, Northern California, and Italy.
kill-AH-mih-ter
ki - LAH - me - ter
Philly – but I have a generic East Coast accent.
Nashville, TN, USA all my life
Kilometer: kil-OHM-muh-ter
Kiloliter: KIL-o-lee-ter (but kil-LOL-ee-ter sounds funny)
Caligraphy: cal-IH-gra-fee
Kahlua: kah-LOO-ah
Kill-o-bot: Kill-o-bot
Currently Atlanta, GA, but born and raised in Yorkshire, England.
Ki-Lom-ih-tuh.
Canadian (of British heritage, if that makes any diff); British Columbia; kill-OHM-muh-ter.
It bugs the hell out of me when people (mostly the radio and TV types) say “kilo-meeter,” which seems more and more to be the standard pronounciation on air here. I know you say “meteer” for ‘metre,’ singular, but something deep within me just wants kilometre and thermometer to rhyme. So there.
Raised in SoCal (LA area) & pronounce the word as kill-AH-mih-ter, although I pronounced it kill-oh-meter in gradeschool until someone corrected me.
So, do tell - what is your hypothesis, Polycarp?? 
Virginia Beach, VA
Kill-OM-eeter
Virginia Beach, VA
Kill-OM-eter
born and raised in detroit, mi. pronounce it Kill-ohm-idder.
Lexington, Ky
Ki-Lom-ih-ter
It may be worth noting that people from around here frequently don’t believe I am due to the way I speak. Same for the rest of my family.
Douglas, Isle of Man, UK
Used to pronounce Kilo MEE ter. But have heard Kil OM iter so often I have switched.
in american english, there’s not a big difference between a short a and a short o when used medially in some situations. an “ahm” sound and an “ohm” sound are nearly identical in a lot of dialects.
Lived in Ohio from birth to 30, in California for 5 years now.
kill-AHM-eter
Dallas, TX - born and raised.
Kill-ahh-mah-ter.
(said with a really cute Texas twang) 
Raised in Ohio, spent my 20s in Pennsylvania, slogging through my 30s in Washington state. Kil-AH-me-der. (Is it possible to make a schwa in these reply boxes?)
Raised all over the South; father from Oregon, mother from Florida.
I say it 'bout-haff-a-MAHL.
Just kidding. “ki-LAH-muh-ter.”
“KILL-oh-MEET-ur”.
Same stress pattern as “HEC-toh-LEET-ur” (hectolitre), “SEK-reh-TAIR-ee” (secretary), etc. I distinctly remember being told that “kil-AH-mih-tur” was incorrect.
Born, raised, and lived all my life in Southern Ontario, Canada, within three driving hours of Toronto.