---
acl_categories:
- '@tdigest'
- '@write'
arguments:
- name: key
  type: key
- name: compression
  optional: true
  token: COMPRESSION
  type: integer
categories:
- docs
- develop
- stack
- oss
- rs
- rc
- oss
- kubernetes
- clients
complexity: O(1)
description: Allocates memory and initializes a new t-digest sketch
group: tdigest
hidden: false
linkTitle: TDIGEST.CREATE
module: Bloom
railroad_diagram: /images/railroad/tdigest.create.svg
since: 2.4.0
stack_path: docs/data-types/probabilistic
summary: Allocates memory and initializes a new t-digest sketch
syntax_fmt: "TDIGEST.CREATE key [COMPRESSION\_compression]"
title: TDIGEST.CREATE
---
Allocates memory and initializes a new t-digest sketch.

## Required arguments

<details open><summary><code>key</code></summary> 

is the key name for this new t-digest sketch.
</details>

## Optional arguments

<details open><summary><code>COMPRESSION compression</code></summary>

is a controllable tradeoff between accuracy and memory consumption. 100 is a common value for normal uses and also the default if not specified. 1000 is more accurate. For more information on scaling of accuracy versus the compression value see [_The t-digest: Efficient estimates of distributions_](https://www.sciencedirect.com/science/article/pii/S2665963820300403).
</details>

## Example

{{< highlight bash >}}
redis> TDIGEST.CREATE t COMPRESSION 100
OK
{{< / highlight >}}

## Redis Software and Redis Cloud compatibility

| Redis<br />Software | Redis<br />Cloud | <span style="min-width: 9em; display: table-cell">Notes</span> |
|:----------------------|:-----------------|:------|
| <span title="Supported">&#x2705; Supported</span><br /> | <span title="Supported">&#x2705; Flexible & Annual</span><br /><span title="Supported">&#x2705; Free & Fixed</nobr></span> |  |

## Return information

{{< multitabs id="tdigest-create-return-info" 
    tab1="RESP2" 
    tab2="RESP3" >}}

One of the following:

* [Simple string reply]({{< relref "/develop/reference/protocol-spec#simple-strings" >}}) `OK` if executed correctly.
* [Simple error reply]({{< relref "/develop/reference/protocol-spec#simple-errors" >}}) in these cases: incorrect key type or incorrect keyword.

-tab-sep-

One of the following:

* [Simple string reply]({{< relref "/develop/reference/protocol-spec#simple-strings" >}}) `OK` if executed correctly.
* [Simple error reply]({{< relref "/develop/reference/protocol-spec#simple-errors" >}}) in these cases: incorrect key type or incorrect keyword.

{{< /multitabs >}}