---
title: Counts (v1.1)
description: API reference for qiskit.result.Counts in qiskit v1.1
source: https://eu-de.quantum.cloud.ibm.com/docs/en/api/qiskit/1.1/qiskit.result.Counts
---

# Counts

*class* `qiskit.result.Counts(data, time_taken=None, creg_sizes=None, memory_slots=None)`

[GitHub](https://github.com/Qiskit/qiskit/tree/stable/1.1/qiskit/result/counts.py#L27-L189)

Bases: [`dict`](https://docs.python.org/3/library/stdtypes.html#dict)

A class to store a counts result from a circuit execution.

Build a counts object

**Parameters**

- **data** ([*dict*](https://docs.python.org/3/library/stdtypes.html#dict)) –

  The dictionary input for the counts. Where the keys represent a measured classical value and the value is an integer the number of shots with that result. The keys can be one of several formats:

  > - A hexadecimal string of the form `'0x4a'`
  > - A bit string prefixed with `0b` for example `'0b1011'`
  > - A bit string formatted across register and memory slots. For example, `'00 10'`.
  > - A dit string, for example `'02'`. Note for objects created with dit strings the `creg_sizes` and `memory_slots` kwargs don’t work and [`hex_outcomes()`](#qiskit.result.Counts.hex_outcomes "qiskit.result.Counts.hex_outcomes") and [`int_outcomes()`](#qiskit.result.Counts.int_outcomes "qiskit.result.Counts.int_outcomes") also do not work.

- **time\_taken** ([*float*](https://docs.python.org/3/library/functions.html#float)) – The duration of the experiment that generated the counts in seconds.

- **creg\_sizes** ([*list*](https://docs.python.org/3/library/stdtypes.html#list)) – a nested list where the inner element is a list of tuples containing both the classical register name and classical register size. For example, `[('c_reg', 2), ('my_creg', 4)]`.

- **memory\_slots** ([*int*](https://docs.python.org/3/library/functions.html#int)) – The number of total `memory_slots` in the experiment.

**Raises**

- [**TypeError**](https://docs.python.org/3/library/exceptions.html#TypeError) – If the input key type is not an `int` or `str`.
- [**QiskitError**](/docs/api/qiskit/1.1/exceptions#qiskit.exceptions.QiskitError "qiskit.exceptions.QiskitError") – If a dit string key is input with `creg_sizes` and/or `memory_slots`.

## Attributes

### bitstring\_regex

Default value: `re.compile('^[01\\s]+$')`

## Methods

### clear

`clear() → None.  Remove all items from D.`

### copy

`copy() → a shallow copy of D`

### fromkeys

`fromkeys(value=None, /)`

Create a new dictionary with keys from iterable and values set to value.

### get

`get(key, default=None, /)`

Return the value for key if key is in the dictionary, else default.

### hex\_outcomes

`hex_outcomes()`

[GitHub](https://github.com/Qiskit/qiskit/tree/stable/1.1/qiskit/result/counts.py#L137-L158)

Return a counts dictionary with hexadecimal string keys

**Returns**

**A dictionary with the keys as hexadecimal strings instead of**

bitstrings

**Return type**

[dict](https://docs.python.org/3/library/stdtypes.html#dict)

**Raises**

[**QiskitError**](/docs/api/qiskit/1.1/exceptions#qiskit.exceptions.QiskitError "qiskit.exceptions.QiskitError") – If the Counts object contains counts for dit strings

### int\_outcomes

`int_outcomes()`

[GitHub](https://github.com/Qiskit/qiskit/tree/stable/1.1/qiskit/result/counts.py#L160-L180)

Build a counts dictionary with integer keys instead of count strings

**Returns**

A dictionary with the keys as integers instead of bitstrings

**Return type**

[dict](https://docs.python.org/3/library/stdtypes.html#dict)

**Raises**

[**QiskitError**](/docs/api/qiskit/1.1/exceptions#qiskit.exceptions.QiskitError "qiskit.exceptions.QiskitError") – If the Counts object contains counts for dit strings

### items

`items() → a set-like object providing a view on D's items`

### keys

`keys() → a set-like object providing a view on D's keys`

### most\_frequent

`most_frequent()`

[GitHub](https://github.com/Qiskit/qiskit/tree/stable/1.1/qiskit/result/counts.py#L118-L135)

Return the most frequent count

**Returns**

The bit string for the most frequent result

**Return type**

[str](https://docs.python.org/3/library/stdtypes.html#str)

**Raises**

[**QiskitError**](/docs/api/qiskit/1.1/exceptions#qiskit.exceptions.QiskitError "qiskit.exceptions.QiskitError") – when there is >1 count with the same max counts, or an empty object.

### pop

`pop(k[, d]) → v, remove specified key and return the corresponding value.`

If key is not found, default is returned if given, otherwise KeyError is raised

### popitem

`popitem()`

Remove and return a (key, value) pair as a 2-tuple.

Pairs are returned in LIFO (last-in, first-out) order. Raises KeyError if the dict is empty.

### setdefault

`setdefault(key, default=None, /)`

Insert key with a value of default if key is not in the dictionary.

Return the value for key if key is in the dictionary, else default.

### shots

`shots()`

[GitHub](https://github.com/Qiskit/qiskit/tree/stable/1.1/qiskit/result/counts.py#L187-L189)

Return the number of shots

### update

`update([E, ]**F) → None.  Update D from dict/iterable E and F.`

If E is present and has a .keys() method, then does: for k in E: D\[k] = E\[k] If E is present and lacks a .keys() method, then does: for k, v in E: D\[k] = v In either case, this is followed by: for k in F: D\[k] = F\[k]

### values

`values() → an object providing a view on D's values`