# Expressions and operators — Bitwise shift operators

> The bitwise shift operators take two operands: the first is a quantity to be shifted, and the second specifies the number of bit positions by which the first operand is to be shifted.

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The bitwise shift operators take two operands: the first is a quantity to be shifted, and the second specifies the number of bit positions by which the first operand is to be shifted. The direction of the shift operation is controlled by the operator used.

Shift operators convert their operands to thirty-two-bit integers and return a result of either type {{jsxref("Number")}} or {{jsxref("BigInt")}}: specifically, if the type of the left operand is {{jsxref("BigInt")}}, they return {{jsxref("BigInt")}}; otherwise, they return {{jsxref("Number")}}.

The shift operators are listed in the following table.

Bitwise shift operators Operator Description Example Left shift(&amp;#x3C;&amp;#x3C;) This operator shifts the first operand the specified number of bits to the left. Excess bits shifted off to the left are discarded. Zero bits are shifted in from the right. 9&amp;#x3C;&amp;#x3C;2 yields 36, because 1001 shifted 2 bits to the left becomes 100100, which is 36. Sign-propagating right shift (&gt;&gt;) This operator shifts the first operand the specified number of bits to the right. Excess bits shifted off to the right are discarded. Copies of the leftmost bit are shifted in from the left. 9&gt;&gt;2 yields 2, because 1001 shifted 2 bits to the right becomes 10, which is 2. Likewise, -9&gt;&gt;2 yields -3, because the sign is preserved. Zero-fill right shift (&gt;&gt;&gt;) This operator shifts the first operand the specified number of bits to the right. Excess bits shifted off to the right are discarded. Zero bits are shifted in from the left. 19&gt;&gt;&gt;2 yields 4, because 10011 shifted 2 bits to the right becomes 100, which is 4. For non-negative numbers, zero-fill right shift and sign-propagating right shift yield the same result.

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