JSONPath Array Slice — Select Ranges of Elements

Array Slicing in JSONPath

Array slicing extracts a range of elements from an array using the [start:end:step] syntax. It is inspired by Python's slice notation and provides a concise way to select contiguous or evenly spaced elements.

Syntax

$.array[start:end]        // elements from start to end-1
$.array[start:end:step]   // with step interval
$.array[:end]             // from beginning to end-1
$.array[start:]           // from start to the end
$.array[::step]           // every Nth element

Basic Slicing

Given:

{
  "numbers": [10, 20, 30, 40, 50, 60, 70, 80]
}

• $.numbers[0:3] returns [10, 20, 30] — first three elements
• $.numbers[2:5] returns [30, 40, 50] — elements at index 2, 3, 4
• $.numbers[-3:] returns [60, 70, 80] — last three elements
• $.numbers[:4] returns [10, 20, 30, 40] — first four elements

Using Step

The step parameter controls the interval between selected elements:

• $.numbers[::2] returns [10, 30, 50, 70] — every other element
• $.numbers[1::2] returns [20, 40, 60, 80] — every other element starting from index 1
• $.numbers[::-1] returns [80, 70, 60, 50, 40, 30, 20, 10] — reversed array (in implementations that support negative step)

Slice Parameters

Parameter	Default	Description
start	0	Beginning index (inclusive)
end	array length	Ending index (exclusive)
step	1	Interval between elements

Practical Patterns

• Pagination: $.items[0:10] for first page, $.items[10:20] for second page.
• Head/Tail: $.items[:5] (first 5) and $.items[-5:] (last 5).
• Sampling: $.data[::10] to grab every 10th record for quick analysis.