The Royal Navy was bigger, but mostly tied up in North Atlantic and Mediterranean by Germany and Italy. It was this experience that resulted in the post-war decision to decolonise as amicably as possible. Britain hadn't enough resources to be overstretched like that.
The Royal Air Force was bigger too, but of course tied up in homeland defending against Germany (Luftwaffe) which was even bigger.
US and Japan had no air forces like RAF or Luftwaffe then. All Japanese airfighters were navy carrier-borne. All US airfighters were navy carrier-borne or army support aircrafts (USAAF). USAF was founded after World War II.
the RN maybe bigger in tonnage but many of the ships were old, even the biggest aircraft carrier are not as big as IJN fleet carrier and can only carry 50-60 aircrafts on board and the warplanes on board are a joke. The swordfish, a biplane torpedo bomber is so damn slow and the fighter, blackburn skuas top speed is less than 250mph. It only toward the end of WW
2 that the RN replace these obselete aircrafts with newer models.
by the way, there a Imperial Japan Army Air Force during WW2. here an extract from wikipedia:
Important aircraft used by the Imperial Japanese Army Air Force during the Second Sino-Japanese War and World War II were:
Fighters:
Nakajima Ki-27 中島 キ-27 九七式戦闘機 (Type 97 Fighter?) Nate
Nakajima Ki-43 中島 キ-43 一式戦闘機 隼 (Type 1 Fighter "Hayabusa"?) Oscar
Nakajima Ki-44 中島 キ-44 二式単座戦闘機 鍾馗 (Type 2 Single seat fighter "Shōki"?) Tōjō
Kawasaki Ki-45 Kai 川崎 キ-45改 二式複座戦闘機 屠龍 (Type 2 Two-seat fighter "Toryū"?) Nick
Kawasaki Ki-61 川崎 キ-61 三式戦闘機 飛燕 (Type 3 Fighter "Hien"?) Tony
Nakajima Ki-84 中島 キ-84 四式戦闘機 疾風 (Type 4 Fighter "Hayate"?) Frank
Kawasaki Ki-100 川崎 キ-100 五式戦闘機 (Type 5 Fighter?)
Mitsubishi Ki-109 三菱 キ-109 試作特殊防空戦闘機 (Experimental heavy fighter interceptor?)
Bombers:
Mitsubishi Ki-21 三菱 キ-21 九七式重爆撃機 (Type 97 Heavy Bomber?) Sally
Mitsubishi Ki-30 三菱 キ-30 九七式軽爆撃機 (Type 97 Light bomber?) Ann
Kawasaki Ki-32 川崎 キ-32 九八式軽爆撃機, (Type 98 Light bomber?) Mary
Kawasaki Ki-48 川崎 キ-48 九九式双発軽爆撃機 (Type 99 Twin-engined light bomber?) Lily
Nakajima Ki-49 中島 キ-49 一〇〇式重爆撃機 呑龍 (Type 100 Heavy bomber "Donryū"?) Helen
Mitsubishi Ki-67 三菱 キ-67 四式重爆撃機 飛龍 (Type 4 Heavy bomber "Hiryū"?) Peggy
Forward air control aircraft:
Mitsubishi Ki-51 三菱 キ-51 九九式襲撃機/軍偵察機 (Type 99 Assault plane/Reconnaissance plane?) Sonia
Kawasaki Ki-102 川崎 キ-102 四式襲撃機 (Type 4 Assault plane?) Randy
Transports:
Nakajima Ki-34 中島 キ-34 九七式輸送機 (Type 97 Transporter?) Thora
Kawasaki Ki-56 川崎 キ-56 一式貨物輸送機 (Type 1 Cargo aircraft?) Thalia
Mitsubishi Ki-57 三菱 キ-57 一〇〇式輸送機 (Type 100 Transporter?) Topsy
Kokusai Ki-59 国際 キ-59 一式輸送機 (Type 1 Transporter?) Theresa
Reconnaissance Planes:
Mitsubishi Ki-15 三菱 キ-15 九七式司令部偵察機 (Type 97 Army HQ reconnaissance plane?) Babs
Tachikawa Ki-36 立川 キ-36 九八式直接協同偵察機 (Type 98 Reconnaissance plane?) Ida
Mitsubishi Ki-46 三菱 キ-49 一〇〇式司令部偵察機 (Type 100 Army HQ reconnaissance plane?) Dinah
Trainers:
Tachikawa Ki-9 立川 キ-9 九五式一型練習機 (Type 95 Model 1 Intermediate trainer?) Spruce
Tachikawa Ki-17 立川 キ-17 九五式三型練習機 (Type 95 Model 3 Basic trainer?) Cedar
Tachikawa Ki-54 立川 キ-54 一式双発高等練習機 (Type 1 Twin-engine advanced trainer?) Hickory
Tachikawa Ki-55 立川 キ-55 九九式高等練習機 (Type 99 Advanced trainer?) Ida
Manshū Ki-79 満州 キ-79 二式高等練習機 (Type 2 Advanced trainer?)
Other planes:
Kokusai Ki-76 国際 キ-76 三式指揮連絡機 (Type 3 Command-control/Liaisonal plane?) Stella
Kayaba Ka-1 萱場 カ号観測機 (Ka-Gō Artillery-spotter?)
but r rite about the USAAF, it was the Army Air Corp during WW2. The only prewar US land based fighter i remember is the Curtiss P40 Curtiss Kittyhawk.