September 17
| [[{{#ifeq:17|1|{{#switch:{{#ifeq:9|1|12|{{#expr:9-1}}}} | 1=January | 2=February | 3=March | 4=April | 5=May | 6=June | 7=July | 8=August | 9=September | 10=October | 11=November | 12=December | 1|12|{{#expr:9-1}}}}
}} {{#switch:{{#ifeq:9|1|12|{{#expr:9-1}}}} |
1=31 | 2=29 | 3=31 | 4=30 | 5=31 | 6=30 | 7=31 | 8=31 | 9=30 | 10=31 | 11=30 | 12=31 | 1|12|{{#expr:9-1}}}}
}} |
{{#switch:9 | 1=January | 2=February | 3=March | 4=April | 5=May | 6=June | 7=July | 8=August | 9=September | 10=October | 11=November | 12=December | 9
}} {{#expr:17-1}}}}|yesterday]] |
[[{{#ifeq:17|{{#switch:9 | 1=31 | 2=29 | 3=31 | 4=30 | 5=31 | 6=30 | 7=31 | 8=31 | 9=30 | 10=31 | 11=30 | 12=31 | 9
}} |
12|1|{{#expr:9+1}}}} | 1=January | 2=February | 3=March | 4=April | 5=May | 6=June | 7=July | 8=August | 9=September | 10=October | 11=November | 12=December | 12|1|{{#expr:9+1}}}}
}} 1|{{#switch:9 |
1=January | 2=February | 3=March | 4=April | 5=May | 6=June | 7=July | 8=August | 9=September | 10=October | 11=November | 12=December | 9
}} {{#expr:17+1}}}}|tomorrow]] | |||||
}
|- |[[{{#switch:{{#if:9| {{#switch:{{#expr: 9 + -1}} |0=12 |13=1 |{{#expr: 9 + -1}} }} |}}{{#if:| {{#switch:{{{daysinmonth}}} |1=31 |2=29 |3=31 |4=30 |5=31 |6=30 |7=31 |8=31 |9=30 |10=31 |11=30 |12=31 | }}|}}{{#if:|{{#ifeq:{{#expr: ({{{isnextmonth}}} + -1) > Template:Cal-date/offset2 }}|1|1|}}|}}{{#if:|{{#ifeq:{{#expr: ({{{isprevmonth}}} + -1) < 1}}|1|1|}}|}}{{#if:|{{#if:Template:Cal-date/offset2Template:Cal-date/offset2|Template:Cal-date/offset2|{{{getoffsetmonth}}}}}|}}{{#if:|{{#if:Template:Cal-date/offset2Template:Cal-date/offset2|{{#if:Template:Cal-date/offset2|Template:Cal-date/offset2|1}}|pew{{#expr: {{{getoffsetday}}} + -1}}}}|}} |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |{{#if:9| {{#switch:{{#expr: 9 + -1}} |0=12 |13=1 |{{#expr: 9 + -1}} }} |}}{{#if:| {{#switch:{{{daysinmonth}}} |1=31 |2=29 |3=31 |4=30 |5=31 |6=30 |7=31 |8=31 |9=30 |10=31 |11=30 |12=31 | }}|}}{{#if:|{{#ifeq:{{#expr: ({{{isnextmonth}}} + -1) > Template:Cal-date/offset2 }}|1|1|}}|}}{{#if:|{{#ifeq:{{#expr: ({{{isprevmonth}}} + -1) < 1}}|1|1|}}|}}{{#if:|{{#if:Template:Cal-date/offset2Template:Cal-date/offset2|Template:Cal-date/offset2|{{{getoffsetmonth}}}}}|}}{{#if:|{{#if:Template:Cal-date/offset2Template:Cal-date/offset2|{{#if:Template:Cal-date/offset2|Template:Cal-date/offset2|1}}|pew{{#expr: {{{getoffsetday}}} + -1}}}}|}} }}|«]] | colspan="5" align="center"| [[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }}]] |[[{{#switch:{{#if:9| {{#switch:{{#expr: 9 + 1}} |0=12 |13=1 |{{#expr: 9 + 1}} }} |}}{{#if:| {{#switch:{{{daysinmonth}}} |1=31 |2=29 |3=31 |4=30 |5=31 |6=30 |7=31 |8=31 |9=30 |10=31 |11=30 |12=31 | }}|}}{{#if:|{{#ifeq:{{#expr: ({{{isnextmonth}}} + 1) > Template:Cal-date/offset2 }}|1|1|}}|}}{{#if:|{{#ifeq:{{#expr: ({{{isprevmonth}}} + 1) < 1}}|1|1|}}|}}{{#if:|{{#if:Template:Cal-date/offset2Template:Cal-date/offset2|Template:Cal-date/offset2|{{{getoffsetmonth}}}}}|}}{{#if:|{{#if:Template:Cal-date/offset2Template:Cal-date/offset2|{{#if:Template:Cal-date/offset2|Template:Cal-date/offset2|1}}|pew{{#expr: {{{getoffsetday}}} + 1}}}}|}} |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |{{#if:9| {{#switch:{{#expr: 9 + 1}} |0=12 |13=1 |{{#expr: 9 + 1}} }} |}}{{#if:| {{#switch:{{{daysinmonth}}} |1=31 |2=29 |3=31 |4=30 |5=31 |6=30 |7=31 |8=31 |9=30 |10=31 |11=30 |12=31 | }}|}}{{#if:|{{#ifeq:{{#expr: ({{{isnextmonth}}} + 1) > Template:Cal-date/offset2 }}|1|1|}}|}}{{#if:|{{#ifeq:{{#expr: ({{{isprevmonth}}} + 1) < 1}}|1|1|}}|}}{{#if:|{{#if:Template:Cal-date/offset2Template:Cal-date/offset2|Template:Cal-date/offset2|{{{getoffsetmonth}}}}}|}}{{#if:|{{#if:Template:Cal-date/offset2Template:Cal-date/offset2|{{#if:Template:Cal-date/offset2|Template:Cal-date/offset2|1}}|pew{{#expr: {{{getoffsetday}}} + 1}}}}|}} }}|»]] |- |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 1|1]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 2|2]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 3|3]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 4|4]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 5|5]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 6|6]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 7|7]] |- |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 8|8]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 9|9]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 10|10]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 11|11]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 12|12]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 13|13]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 14|14]] |- |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 15|15]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 16|16]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 17|17]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 18|18]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 19|19]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 20|20]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 21|21]] |- |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 22|22]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 23|23]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 24|24]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 25|25]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 26|26]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 27|27]] |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 28|28]] |- |[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 29|29]] |{{#ifeq:9|2||[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 30|30]]}} |{{#ifeq:{{#if:| {{#switch:{{#expr: {{{monthoffset}}} + 0}} |0=12 |13=1 |{{#expr: {{{monthoffset}}} + 0}} }} |}}{{#if:9| {{#switch:9 |1=31 |2=29 |3=31 |4=30 |5=31 |6=30 |7=31 |8=31 |9=30 |10=31 |11=30 |12=31 | }}|}}{{#if:|{{#ifeq:{{#expr: ({{{isnextmonth}}} + 0) > Template:Cal-date/offset2 }}|1|1|}}|}}{{#if:|{{#ifeq:{{#expr: ({{{isprevmonth}}} + 0) < 1}}|1|1|}}|}}{{#if:|{{#if:Template:Cal-date/offset2Template:Cal-date/offset2|Template:Cal-date/offset2|{{{getoffsetmonth}}}}}|}}{{#if:|{{#if:Template:Cal-date/offset2Template:Cal-date/offset2|{{#if:Template:Cal-date/offset2|Template:Cal-date/offset2|1}}|pew{{#expr: {{{getoffsetday}}} + 0}}}}|}}|31|[[{{#switch:9 |1=January |2=February |3=March |4=April |5=May |6=June |7=July |8=August |9=September |10=October |11=November |12=December |9 }} 31|31]]|}} | colspan="4"| |}
{{#if:||}}
- ???? —Valeria Castillo (Latin-American Spanish voice of Thunderblast) is born.
- 1923 — Musician Hank Williams is born.
- 1955 — Satō Vinyl Industries, Ltd., which would later become Takara, is formed in Japan.
- 1958 — Sander de Heer (Dutch voice of Starscream) is born.
- 1984 — Barbora Šedivá (Cezch voice of Charlie Watson) is born.
- 1984 — The original Transformers cartoon series premieres with the episode "More than Meets the Eye, Part 1" in the United States.
- 1984 — The Transformers arrive on Earth for the first time. Secret Legacy, Part 1
- 1985 — Nicolas Matthys (French voice of Heatwave, Croaton and more) is born.
- 1986 — The Transformers episode "Five Faces of Darkness, Part 3" premieres in the U.S.
- 1987 — Family Home Entertainment releases The Transformers: The Movie and "The Return of Optimus Prime, Part 1" on VHS and Beta in the U.S.
- 1988 — The Transformers #184: "Space Pirates!" is released in the UK by Marvel Comics.
- 1994 — The Generation 2 episode "Masquerade" premieres in Germany.
- 2001 — Beast Wars — The Beginning: Vol. 4 is released on VHS in the UK by Universal.
- 2001 — The Robots in Disguise episode "Secret Weapon: D-5" premieres in the U.S.
- 2003 — Armada Volume 2: Fortress TPB is released by Dreamwave Productions.
- 2003 — Armada: The Awakening and The Quest are released in the U.S. by DK Publishing.
- 2004 — The Super Link episode "Laserwave's Last Moments" premieres in Japan.
- 2005 — The Cybertron episode "Race" premieres in the U.S.
- 2005 — The Galaxy Force episode "And So, It Is Time to Go on a Journey" premieres in Japan.
- 2008 — "I, Lowtech" is released through the Fun Publications Official Transformers Collectors' Club members-only section.
- 2008 — All Hail Megatron #3 and Spotlight Volume 3 TPB are released by IDW Publishing.
- 2008 — The Animated episode "Survival of the Fittest" premieres in France.
- 2011 — The Prime episode "Darkness Rising, Part 2" premieres in Italy.
- 2011 — The Prime episode "Stronger, Faster" premieres on Hub Network.
- 2012 — The Prime episode "Predatory" premieres in Indonesia.
- 2013 — The Prime episode "Synthesis" premieres in Hungary.
- 2014 — More than Meets the Eye #33 and Phase One Omnibus are released by IDW Publishing.
- 2015 — The Robots in Disguise episode "Lockout" premieres in Italy.
- 2015 — The Robots in Disguise episode "Similarly Different" premieres in Poland.
- 2016 — The 99th Rescue Bots episode, "Cody's 11", premieres in the U.S., officially making Rescue Bots the longest-running Transformers cartoon.
- 2016 — The Rescue Bots episode "Unfinished Business" premieres in Hungary.
- 2016 — The Robots in Disguise episode "Strongarm's Big Score" premieres in Canada on Teletoon.
- 2017 — Carlos Íñigo (Latin-American Spanish voice of Waspinator and Side Burn) dies at age 56.
- 2019 — The Cyberverse episode "The Visitor" premieres in Germany.
- 2019 — The Cyberverse episodes "Perfect Storm" and "The Crossroads" premiere in Australia and New Zealand.
- 2021 — The Cyberverse episodes "Battle For Cybertron I" through "The Sleeper" premiere in Brazil.
- 2022 — Carlos Comério (Brazilian voice of Oracle) dies at age 56 from lung cancer.
- 2023 — The Beast Wars Again episode "Rhinox Rampages! (Part 1)" airs on TV Tokyo.
- 2023 — The EarthSpark episode "A Stygi Situation" premieres in France.
- 2023 — The EarthSpark episode "What Dwells Within" premieres in Hungary.
- 2024 — Transformers Day 2024.
- 2025 — G.I. Joe #11 is released by Image Comics and Skybound Entertainment.
- 2025 — The Cyberworld episode "Storm the Desert" premieres on YouTube.
- 2025 — Transformers Day 2025, preorders for many of the first wave of Studio Series of 2026 go up.