Measuring boule to jack

Determining which boule is closest to the jack is at the heart of petanque. There are a number of different ways to do it.

(1) VISUAL INSPECTION (aka “eye-balling”)

Visual inspection is the technique of first resort.

There is a trick to being able to look at the game on the ground and tell which of two boules is closer to the jack. The trick is in where you stand.  Imagine a straight line drawn between the boules, and a perpendicular line drawn away from its center.  You want to  stand back a bit from the boules, somewhere on that imaginary perpendicular line.  In most cases, from this angle, you will be able to see that the jack is closer to one of the boules.  Some people prefer to look across the boules to the jack, while others prefer to look across the jack toward the two boules. When in doubt, try doing  both.

Visual inspection is quick, and there is no danger (as with a tape measure) of accidentally touching and moving a boule or the jack.  On the other hand, it is not precise.  When two boules are almost the same distance from the jack, it can be impossible to tell which is closer simply by visual inspection.


In comparison we use some physical object whose length can be adjusted to compare the distances between the boules and the jack.  Various objects can be used to make the comparison. The traditional Provençal method is to hold two sticks together, as in the photo below.  A telescoping metal rod, like an old radio antenna, a pointer, or a magnetic boule lifter, also works nicely.

Chopstick calipers – a modern version of a traditional Provençal technique

Another traditional technique is to use a piece of string, as in the picture below.  It is not a reliable technique.  It is amazing how much the string mysteriously stretches depending on whose boules are being measured. Thanks to the Brighton-Hove Petanque Club for several photos, includeing the next three.

One of the best comparison tools is a folding rule with an extensible end piece.

A locking tape measure can be used as an effective comparison tool. Ignore the numbers on the tape. Extend it between the boule and jack, and lock it.

The most precise tool for comparing small distances is a set of calipers.

Some tape measures have a small built-in set of calipers.
A folding rule can be used as a calipers.

Unfortunately, comparison isn’t practical for longer distances. For those distances, we need to measure.


The third technique is to measure the distances between the jack and the relevant boules, and then to compare the measurements.  (Measurement involves assigning numeric values to distances, which comparison does not.)  The most common tool for measuring is a retractable steel tape measure. (See our post on buying a tape measure.)

Measurement works well for long distances, but it is difficult to do.  It requires squatting or kneeling and holding the tape measure steady, with two different parts of the tape microscopically close to boule and jack (but without touching or moving either of them), then reading the numbers on the tape to the precision of one millimeter (while avoiding distortions due to parallax).  It requires strong legs, steady hands, and good eyes.  And of course, it involves placing a tape measure so close to the jack and the boules that bumping and moving one of them becomes a real danger.


Le Juge – a visual inspection device for petanque

New technology is making visual inspection more precise.

The first advance in this area occurred around the year 2000, with a device called Le Juge (the Judge). It was essentially a magnifying glass with concentric lines engraved on it. You centered the view on the jack, and the concentric rings made it easy to determine the relative distances of the boules to the jack.


Le Juge worked pretty well, but it was never widely used. Almost immediately it was made obsolete by a similar idea implemented in far superior technology — smartphone apps.

There are a number of smartphone apps, available on both iPhone and Android platforms.

Device-assisted visual inspection has a lot of advantages over other methods. It is quick, easy, and precise. There is no risk of touching and moving boules or jack. You don’t need to squat or get down on your knees. It requires a smartphone, but smartphones are becoming ubiquitous. (See also our post on smartphone apps for measuring.)

Another device for visual inspection is a laser “tape measure”. These devices are widely used in construction, but as devices for making petanque measurements they are clumsy. A laser beam can’t see though intervening boules, or through rocks or bumps on the terrain. And a laser tape measure is pretty expensive compared to a $10 steel tape measure.

Some finer points

Before we end, we should mention a couple of the finer points of the art of measuring.

wedges_and_calipersWhen the distances are close and an umpire wants to make sure that nothing is disturbed during the measuring, he/she can place wedges under boules. In this YouTube video we can see the umpire placing wedges and the measuring with calipers. It looks like she is measuring the “second” boules to determine whether the winning team scored one point or two.

feeler_gauge_spread_outAnother standard item in an umpire’s toolkit is a set of feeler gauges, the kind that you would use when gapping spark plugs. An umpire will use them when there is daylight between boule and jack but they are so close that you can’t fit a calipers between them.



  1. Measuring distance between boules and the cochonnet by former Southern Counties Petanque Association Regional Umpire Richard Powell. (Also available HERE.)
  2. The Umpire’s Training Manual by Petanque New Zealand
  3. A guide to measures by Pen-Y-Coed petanque


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