Use the official 5th Edition Dungeons & Dragons Spell Slot Calculator to quickly determine how many spell slots your character has based on their class level and casting ability (Full, Half, or Third Caster).
5e Spell Slot Calculator
5e Spell Slot Calculation Method
The number of spell slots in D&D 5th Edition is determined by the class’s Spellcasting feature, which follows a Level vs. Slot Tier structure based on the **Effective Caster Level**.
$$\text{Effective Level} = \text{Character Level} \times \text{Casting Factor}$$
- Full Caster (Factor 1.0): Effective Level = Character Level
- Half Caster (Factor 0.5): Effective Level = $\lfloor \text{Character Level} / 2 \rfloor$ (rounded down)
- Third Caster (Factor 0.33): Effective Level = $\lfloor \text{Character Level} / 3 \rfloor$ (rounded down)
The resulting Effective Level is then cross-referenced with the standard Full Caster Spell Slot Table:
| Lvl | 1st | 2nd | 3rd | 4th | 5th | 6th | 7th | 8th | 9th |
|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | – | – | – | – | – | – | – | – |
| 5 | 4 | 3 | 2 | – | – | – | – | – | – |
| 10 | 4 | 3 | 3 | 3 | 2 | – | – | – | – |
| 15 | 4 | 3 | 3 | 3 | 2 | 1 | 1 | 1 | – |
| 20 | 4 | 3 | 3 | 3 | 3 | 2 | 2 | 1 | 1 |
Note: This table is an excerpt. Full casters use their actual level. Half/Third casters use their derived effective level.
Formula Source: Wizards of the Coast – D&D Basic Rules (Official) | Roll20 5e Compendium
Variables Explanation:
- Character Level: The current level of your character (1-20). This is the primary input for determining progression.
- Caster Type: Defines your class’s ability to cast spells. Full Casters progress fastest, Half Casters (like Paladins) progress slower, and Third Casters (subclasses like Arcane Trickster) progress the slowest.
Related D&D Calculators
What is a 5e Spell Slot?
A spell slot in Dungeons & Dragons 5th Edition represents the magical energy a character can expend to cast a spell. Unlike earlier editions, 5e does not require players to memorize a specific spell into a specific slot. Instead, a spell slot is a generic resource of a certain level (1st through 9th) that can be used to cast any spell the character knows or prepares, provided the spell’s level is equal to or lower than the slot’s level.
For instance, a character with a 3rd-level spell slot can cast any 1st-level, 2nd-level, or 3rd-level spell, often granting additional benefits if the spell is “cast at a higher level.” The total number of available spell slots increases as the character’s class level increases, following the progression outlined in the class tables in the Player’s Handbook.
How to Calculate Spell Slots (Example)
- Determine Character Level and Caster Type: Assume a player has a **Level 8 Paladin**. Paladins are Half Casters.
- Calculate Effective Caster Level: A Paladin’s Effective Caster Level is their character level divided by two, rounded down. $\lfloor 8 / 2 \rfloor = 4$. The effective level is 4.
- Lookup Spell Slots: Use the Full Caster table (like the one above) but look at the row corresponding to **Level 4**.
- Identify Slots: The slots for a Level 4 Full Caster are: 4 1st-level slots and 3 2nd-level slots. The Paladin (Half Caster) at Level 8 has **4/3/0/0/0/0/0/0/0** slots.
Frequently Asked Questions (FAQ)
Q: Does my spellcasting ability score (e.g., Intelligence, Wisdom) affect the *number* of spell slots I have?
A: No. Your spellcasting ability modifier only affects your Spell Save DC and your Spell Attack Modifier. The *number* of spell slots is solely determined by your class level and caster type.
Q: Are Warlocks Full Casters?
A: Warlocks are unique. They use a system called Pact Magic, which grants fewer, but higher-level slots that refresh on a short rest. The main 5e Spell Slot Calculator table does not apply to Warlocks; they are generally considered Non-Casters for this progression.
Q: How do I calculate spell slots if I multiclass?
A: The rule is complex. You add half the levels (rounded down) of your Half-Caster classes and one-third the levels (rounded down) of your Third-Caster classes, plus all the levels of your Full-Caster classes. This total is your final **Effective Caster Level** to look up on the table.
Q: Why does the Half Caster level calculation round down?
A: The rule specifically states you round down any fraction. This ensures you only gain new spell slots when you reach an appropriate milestone (e.g., gaining 2nd-level slots at effective level 3, which requires a Half Caster to be at character level 5 or 6).