How to say "fifty-fifty" in Japanese

• 半々はんはんCommon
  no-adjectiveCovers the literal sense of something being divided half and half, such as costs, time, or a mixture. The most natural everyday choice for an actual even split.
  二ふたつのグループが半々はんはんに同社どうしゃを所有しょゆうしている。↗

  The two groups share equally in the company.
• フィフティーフィフティーCommon
  nounThe direct loanword for 'fifty-fifty', used in casual speech for an even split or even odds with the same feel as the English phrase.
• 五分五分ごぶごぶCommon
  no-adjectiveA yojijukugo meaning the chances are as likely as not, or that two sides are evenly matched. Best for even odds in a contest or situation rather than splitting something in half.
  鯨くじらが今世紀こんせいきの終おわりに死に絶しにたえる可能性かのうせいは五ご分ふん五ご分ふんである。↗

  As likely as not, whales will be extinct by the end of this century.

Use 半々 for a literal even split or mix, 「フィフティーフィフティー」 for the casual loanword feel of 'fifty-fifty', and 五分五分 when talking about even odds or an even match between sides.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 半々はんはんhalf and half
• フィフティーフィフティーfifty-fifty
• 五分五分ごぶごぶas likely as not