Plan Your Day Around Duolingo Hearts and Energy
Five hearts or 25 energy — either way, Duolingo puts a limit on how much you can study in one sitting. This planner works out how far your hearts or energy will stretch today, and the cheapest way to keep going when they run out.
What your app shows right now
Fill in what you can see in Duolingo. Everything is worked out in your browser; nothing is uploaded.
Your plan for today
Your options, cheapest first
Three worked examples
Try these in the planner above to see how the numbers move.
Example 1 — Hearts: full hearts, 2 lessons, 3 mistakes each
You have 5 hearts and need 6 for 2 lessons at 3 mistakes each, so you can finish 1 lesson and are 1 heart short. That is 25 minutes of waiting, or 1 practice lesson, or about 500 gems for a refill — but a refill only gives you 5 hearts again, so it still covers just 1 lesson. Waiting or practising is the smarter move here.
Example 2 — Energy: full battery, 3 lessons, 10 questions, 90% correct
Three lessons cost 30 energy in questions, but your streaks earn about 9 back, so you need only 21. With a full 25 you are covered, and you finish the day on about 4 energy.
Example 3 — Hearts: 1 heart left, 5 lessons, 1 mistake each
You need 5 hearts and have 1, so you can finish 1 lesson and are 4 hearts short — about 1 hour 40 minutes of waiting at 25 minutes a heart, or 4 practice lessons, or about 500 gems for a full refill, which this time really does cover all 5 lessons.
How the planner works out your day
- Hearts — what today costs. Lessons wanted times mistakes per lesson. Every mistake costs exactly 1 heart, so the maths is simple.
- Hearts — how far you get. Your hearts divided by mistakes per lesson, rounded down. That is the number of lessons you can finish before the meter hits zero.
- Hearts — what is missing. Hearts needed minus hearts you have. The wait is the shortfall times your refill speed; practice lessons give 1 heart each, free; a gem refill fills you to 5, never more.
- Energy — what a lesson costs. One energy per question, whatever the answer. Your correct-answer streaks pay some of it back — about 3 energy for every 5 correct in a row, on average.
- Energy — how far you get. The planner spends your energy lesson by lesson at the net cost, and stops when the next lesson no longer fits. Energy never goes above 25.
- Energy — what is missing. Energy needed minus energy you have. It returns at about 1 an hour, about 4 per rewarded ad, or all at once for gems — about 750 on iPhone, about 350 on Android, and both prices vary.
- Super. Super and Max give unlimited hearts and unlimited energy, so there is nothing to plan around — the planner simply says so.
Hearts vs Energy — the two systems compared
| Hearts (old system) | Energy (current system) | |
|---|---|---|
| Daily allowance | 5 hearts | About 25 energy |
| What drains it | 1 heart per mistake | 1 energy per question, right or wrong |
| Where you see it | Desktop website and some mobile accounts | Android and iPhone apps |
| Free ways back | Waiting (about 25 min a heart, varies) or practice lessons (1 heart each) | Waiting (about 1 an hour), streak bonuses (+1–5 per 5 correct), ads (+3–5), chests (+5) |
| Instant refill | About 450–500 gems for a full refill | About 750 gems (iPhone) or 350 gems (Android) |
| With Super | Unlimited hearts | Unlimited energy |
Hearts and energy questions, answered
Why does my app use Energy while my friend still has Hearts?
Duolingo switched mobile accounts over gradually from mid 2025 and still tests the change on different groups. Some accounts kept Hearts, and the desktop website never changed. You cannot choose — your account shows whichever system Duolingo gave it.
Do wrong answers cost energy?
No, and that is the main difference from Hearts. Energy falls by 1 for every question you answer, right or wrong. A mistake only hurts because it breaks the run of correct answers that earns energy back.
What is the cheapest way to keep going after I run out?
Waiting costs nothing, and practice lessons (Hearts) or rewarded ads (Energy) are free as well. Gems are the quick option, but a full refill is about 500 gems for hearts or 350–750 for energy — that can take a week of casual play to earn back.
How do practice lessons give hearts back?
In the Hearts system, finishing a practice lesson on older material restores 1 heart, free. It is the best free fix when you are only a heart or two short.
Does Super really take the limit away completely?
Yes. Super (and Max) give unlimited hearts and unlimited energy, so a lesson never stops halfway. For someone who studies on a phone every day, that is the main thing Super buys.
Should I wait or spend gems?
Wait, almost every time — unless the session itself matters, like a league push on Sunday or a day you must not lose your streak. Gems are slow to earn and quick to spend; a refill you did not need is gems you will want later.
Keep reading on DuolingoGuides
- Duolingo Energy System Explained: How It Works and Never Running Out →
- Duolingo Hearts: How the System Works →
- What Are Duolingo Gems For? Every Use Explained →
- Duolingo XP vs Gems: Differences and Benefits Explained →
- Is Super Duolingo Worth It? A Comprehensive Review →
- Duolingo Streak Freeze Explained →
- How to Use a Streak Freeze in Duolingo →
- How Much Does a Streak Freeze Cost? →
DuolingoGuides is an independent guides site and is not connected to Duolingo. Refill speeds and gem prices change by account, platform and Duolingo’s tests — always check your own app before spending gems.