Is there a self destruct type spell?

[Yqatuba]

I guess breaking a Staff of the Magi counts as this but it's not a spell.

[Adjoint]

Disintegrate on yourself. Gate a balor. Plane shift to Negative Energy Plane. Also with most AoE spells you can, if you want to, include yourself in the effect. There are many ways to kill yourself. The question is, what do you want to achieve with it?

[Yqatuba]

I mean one that makes you blow up and also does a lot of damage (proportional to your HP perhaps?) to everything around.

[Val'bryn2]

I find those rather poorly thought out spells. How do you practice? It's kind of a one-use spell. They don't have any that I can think of in Pathfinder

[Yqatuba]

I assumed they'ed by used mainly for Heroic Sacrifice type situations. I assume that's usually why you'd break the staff also (since you either die with no save or get sent to another plane with no save if you're "lucky")

[doomman47]

Fireball centered on self?

[Darigaaz the Igniter]

bag of holding + portable hole

[Many Owls]

Maybe Detonate is kinda what you're looking for? Has a sacrificing feel to it, but then again, you aren't 100% dead when you use it.

[Belafon]

The 10th level ability of the Dawnflower Dissident includes a flame strike centered on your body.

A Ring of Retribution can be used as an immediate action. Bonus fun if you are wearing a necklace of fireballs.

The most straightforward way of doing this is to cast deadman’s contingency on yourself with a fireball as the linked spell.

There actually is a spell called “blaze of glory” but it does the exact opposite (heals your allies instead of exploding).