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MINECRAFT

End Portal Finder Calculator — stronghold triangulation from two eye throws

Enter the coordinates and facing angle of two ender eye throws and get the point where the two bearings cross, which is where the stronghold sits.

The facing angle is the first of the two numbers on the F3 debug screen’s Facing line in Java Edition, where 0 points south along positive Z, 90 points west, 180 points north and −90 points east. Throw the eye, stand still, look straight along its flight path, and read the number off the screen.
Used only for the convenience conversion in the results grid, so you can plan the Nether leg of the journey. Eight to one is the Overworld to Nether ratio in the current game.
Estimated stronghold position
 
Distance from throw 2
Crossing angle
Nether coordinates
Distance from throw 1
Tip: the crossing angle is the quality measure. Two throws taken close together give a shallow crossing and a wildly uncertain answer.
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The end portal finder calculator above solves one geometry problem: where do two lines cross? Each ender eye throw gives you a point and a direction, which together define a line pointing at the nearest stronghold. Two such lines from different places intersect at the stronghold. That is the entire method, and everything that can go wrong with it comes from the word different.

Arb Digital builds free calculators that state which version of a system they describe and what makes them fail. This page implements Java Edition conventions, using the facing angle from the F3 debug screen, and it says clearly below where Bedrock Edition and older versions diverge.

What This End Portal Finder Does

It takes two throws. For each one you supply the X and Z coordinates you were standing at and the facing angle you read off the debug screen while looking along the eye’s flight path. It converts each angle into a direction vector, intersects the two resulting lines, and reports the crossing point along with the distance from each throw and the angle at which the two bearings met.

The crossing angle is the output people ignore and should not. It is the only quality measure the method has. Two bearings that meet at a wide angle pin the point down tightly; two that meet at a shallow angle produce an intersection that moves hundreds of blocks for a fraction of a degree of error in either reading. The calculator warns you when the angle is small, because a confident-looking coordinate from a five-degree crossing is worse than no coordinate at all.

Y coordinates are not part of this. Strongholds generate underground and the eye gives no vertical information you can triangulate from, so the answer is a surface position to dig at.

How to Use It

  1. Throw an eye of ender, stand still, and turn until you are looking directly along the line it travelled. Press F3 and read the first number on the Facing line, along with your X and Z.
  2. Travel several hundred blocks sideways relative to the direction the eye went. Perpendicular is ideal; straight along the bearing is useless.
  3. Throw a second eye from the new position and record the same three numbers.
  4. Put both sets into the calculator and read the crossing point.
  5. Check the crossing angle before you set off. Under about ten degrees, go further sideways and throw again rather than trusting the number.

The Formula: How It Is Calculated

Java Edition measures yaw so that 0 points along positive Z, which is south, and the angle increases towards west. A facing angle θ therefore corresponds to the direction vector (−sinθ, cosθ) in the X and Z plane. At θ = 0 that is (0, 1), pointing south; at θ = −90 it is (1, 0), pointing east.

With two points P₁ and P₂ and two direction vectors d₁ and d₂, the intersection is found by solving P₁ + t·d₁ = P₂ + s·d₂. Taking the cross product of the two directions gives the denominator, and t = ((x₂ − x₁)·d₂z − (z₂ − z₁)·d₂x) ÷ (d₁x·d₂z − d₁z·d₂x). The stronghold is then at P₁ + t·d₁.

Work through the defaults. The first throw is at (0, 0) facing −45, giving a direction of (0.7071, 0.7071) — south-east. The second is at (400, 0) facing 45, giving (−0.7071, 0.7071) — south-west. The denominator is 0.7071 × 0.7071 − 0.7071 × (−0.7071) = 1, and t works out at 282.84. Following the first bearing that far lands at X 200, Z 200, which is 282.8 blocks from each throw, with the two bearings crossing at a perfect 90 degrees.

Divided by the Nether ratio of eight, that is X 25, Z 25 in the Nether, which is the useful number if you intend to travel most of the way through a portal.

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Why the Second Throw Must Be Somewhere Else

This is the failure the method is famous for. If both throws are taken from the same place, or from two places along the same bearing, the two lines are the same line and there is no intersection to find. The calculator detects this and refuses to output a coordinate rather than producing a meaningless one.

The near case is more dangerous than the exact case, because it does not obviously fail. Two throws a hundred blocks apart aimed at a stronghold a thousand blocks away cross at a very shallow angle, and the intersection point is extremely sensitive to the accuracy of both angle readings. A tenth of a degree of misreading, which is easy when you are eyeballing the flight path, can move the answer by hundreds of blocks. Wide crossing angles are not a nicety; they are the difference between digging in the right chunk and digging in the wrong biome.

The practical rule is to move perpendicular to the first bearing, and to move far — several hundred blocks at least, more if the eye is climbing steeply, which indicates the stronghold is close and vertical rather than distant and horizontal. If the crossing angle comes out under about ten degrees, the honest response is to take a third throw somewhere else rather than to trust the arithmetic.

Which Version This Describes

Stronghold generation has changed more than once, and the numbers below are the current Java Edition behaviour documented on the Minecraft Wiki stronghold page: 128 strongholds generate across eight concentric rings, with three in the innermost ring between roughly 1,280 and 2,816 blocks from the world origin, and successive rings holding 6, 10, 15, 21, 28, 36 and 9 out to about 24,320 blocks.

That is a large change from older versions, which generated only three strongholds in a single ring. If you are playing on an old version, a very old world, or a modified server, the ring radii and counts may not apply. The triangulation itself still works, because it depends only on where the eye points, but any reasoning you do about expected distance does not.

Bedrock Edition uses a different generation scheme again, and its debug information is presented differently, so treat the angle convention here as a Java Edition assumption. The safest check on any version is that the first throw’s bearing should point roughly away from the origin if you are near spawn, since the innermost ring surrounds it.

What the Eye Itself Tells You

A thrown eye flies about twelve blocks towards the nearest stronghold before falling or breaking, and it has a one in five chance of shattering on each throw according to the wiki’s eye of ender page. Two consequences follow for anyone using this method.

The first is that eyes are a consumable, and the twelve eyes you need to activate the portal are separate from the ones you spend finding it. Budgeting a few spare throws is sensible, and picking up the ones that survive is worth the walk.

The second is the vertical clue. The eye rises when the stronghold is far away and descends when you are within about a dozen blocks of it. If your second throw shows the eye plunging steeply, you are effectively on top of the stronghold and triangulation has already done its job — start digging rather than solving geometry.

One more subtlety: the eye points at the nearest stronghold, and with 128 of them scattered in rings, a long journey between throws can put a different stronghold nearer than the one you were tracking. Keep the two throws within a few hundred blocks of each other and this does not arise; make the second throw thousands of blocks away and it can, producing two bearings to two different structures and an intersection that means nothing.

How This Differs From Our Other Coordinate Tools

Our Nether portal calculator does coordinate scaling: it converts positions between the Overworld and the Nether at the eight to one ratio and checks how far an arrival point sits from an existing portal. It performs no triangulation and knows nothing about bearings, which is why the two pages do not overlap.

The triangulation calculator is the general surveying version of this problem, and it works differently: it takes a baseline length and the interior angles measured at each end, then solves the triangle with the law of sines. This page takes absolute world coordinates and absolute compass-style bearings instead, and it uses the game’s own yaw convention where south is zero, which no surveying tool would do. The azimuth calculator covers real-world bearings between geographic points, where north is zero.

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Common Mistakes to Avoid

  • Taking both throws from nearly the same spot. The bearings barely diverge, the crossing angle collapses, and the answer moves hundreds of blocks for a fraction of a degree of error.
  • Moving along the first bearing instead of across it. Walking towards the stronghold changes the distance but not the angle, so the second throw adds no information at all.
  • Reading the wrong number off the Facing line. The first value is the yaw you want; the second is pitch, which is vertical and has nothing to do with this.
  • Using compass conventions. In Java Edition a facing angle of 0 points south, not north, and the angle increases westward. Entering a real-world bearing gives a confidently wrong answer.
  • Throwing thousands of blocks apart. With 128 strongholds in the world, a long move can put a different one nearest, and the two bearings then point at two different structures.

Related Free Tools From Arb Digital

Plan the journey with the Nether portal calculator for the coordinate scaling, and use the Minecraft circle generator when you get round to building something at the other end. For the general versions of the geometry here, the triangulation calculator solves the surveying form of the same problem, the azimuth calculator handles real-world bearings, the coordinates converter deals with geographic formats, and the 3D coordinate converter covers Cartesian, cylindrical and spherical systems. Everything else is on the free online tools hub.

Frequently Asked Questions

How do I find the end portal with ender eyes?

Throw an eye, stand still, look along its flight path and record your X and Z plus the first number on the F3 Facing line. Move several hundred blocks perpendicular to that bearing, throw again, record the same three numbers, and put both sets into this calculator. The point where the two bearings cross is the stronghold.

Which version of Minecraft does this describe?

Java Edition, using its yaw convention where a facing angle of 0 points south along positive Z and the angle increases westward. Bedrock Edition generates strongholds differently and presents its debug information differently, and older versions generated only three strongholds rather than the current 128.

Why does it fail if both throws are from the same place?

Because two identical or near-identical bearings define the same line, and a line does not intersect itself at a single point. The method is a bearing intersection, so the two throws must be taken from genuinely different places, ideally offset perpendicular to the first bearing.

What crossing angle should I aim for?

As wide as you can get, and preferably well above ten degrees. A shallow crossing makes the intersection extremely sensitive to small errors in either angle reading, so a tenth of a degree of misreading can move the result by hundreds of blocks.

How many strongholds are there?

In current Java Edition, 128 across eight rings, with three in the innermost ring between roughly 1,280 and 2,816 blocks from the origin and the outermost ring reaching about 24,320 blocks. Older versions generated only three in a single ring, so version matters if you are reasoning about expected distance.

Do ender eyes break?

Yes. A thrown eye has a one in five chance of shattering, and an eighty per cent chance of surviving to be picked up again. Budget a few spare eyes for the search on top of the twelve the portal frame needs.

Why is there no Y coordinate in the result?

Because the eye gives no vertical information you can triangulate from, and strongholds generate underground. The output is a surface position to dig at, not a depth.

This page is a geometry tool for a video game. It works from the coordinates and angles you enter, so its accuracy is limited by how precisely you read them, and stronghold generation has changed between game versions — check which version your world uses before relying on any assumption about where strongholds should be.

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