Japanese Slang for "I'm Down" - 5 Natural Ways to Show Interest

When someone suggests doing something together, saying just いいね gets repetitive. Here are the casual phrases Japanese people actually use to show enthusiasm.

The Safe Defaults

いいね！ = "Sounds good!" (always works)
いいよ！ = "Sure!/Okay!" (slightly more casual)

These are your bread and butter. Use them anywhere, anytime.

Action-Focused Responses

やろう！(yarou)

"Let's do it!"

Perfect when someone suggests an activity:

• Friend: "カラオケ行かない？" (Wanna go karaoke?)
• You: "やろう！" (Let's do it!)

Vibe: Enthusiastic, proactive, slightly masculine but fine for everyone

行こう！(ikou) / 行く行く！(iku iku)

"Let's go!" / "I'm going, I'm going!"

行こう = Standard "let's go"
行く行く = Excited "I'm totally going!"

Examples:

• "ボーリング行こうよ！" → "行く行く！"
• "Let's go bowling!" → "I'm totally going!"

行く行く sounds younger and more enthusiastic than 行こう.

Enthusiasm Levels

Low-key agreement:

• いいよ = "Sure" (neutral)
• うん、いいね = "Yeah, sounds good" (agreeable)

Medium enthusiasm:

• いいね！やろう = "Sounds good! Let's do it"
• 行こう行こう = "Let's go, let's go"

High enthusiasm:

• めっちゃいいね！ = "That sounds awesome!"
• 絶対行く！ = "I'm definitely going!"
• やろうやろう！ = "Let's do it, let's do it!"

Situational Usage

For physical activities:

• やろう！ (Let's do it!)
• 行こう！ (Let's go!)

For events/plans:

• 行く行く！ (I'm going!)
• 参加する！ (I'll participate!)

For food/drinks:

• 食べよう！ (Let's eat!)
• 飲もう！ (Let's drink!)

Age and Gender Notes

やろう - Slightly masculine but acceptable for everyone
行く行く - More common among younger people (teens-20s)
いいね/いいよ - Gender-neutral, age-neutral (safest)

Regional Variations

Kansai dialect:

• ええやん！ = "That's good!" (Osaka-style いいね)
• 行こか！ = "Let's go!" (Kansai 行こう)

Tokyo casual:

• やばいね！ = "That's crazy good!" (positive slang)
• 最高じゃん！ = "That's the best!"

Common Combinations

Instead of just one word, combine for natural flow:

• "いいね！やろうやろう！"
• "めっちゃいい！行く行く！"
• "最高！絶対やろう！"

What NOT to Say

❌ はい、します (too formal/stiff)
❌ 同意します (business meeting language)
❌ 賛成です (sounds like you're voting)

✅ やろう！ (natural and enthusiastic)

Quick Reference

Universal safe choices: いいね, いいよ
Show enthusiasm: やろう, 行く行く
Maximum excitement: めっちゃいいね, 絶対行く

Pro tip: Match the energy level of the person suggesting. If they're excited, be excited back. If they're casual, keep it casual.

The key is sounding natural, not textbook. These phrases make you sound like you actually want to join in, not like you're just being polite.