---
title: hypertable_index_size() | Tiger Data Docs
description: Get the disk space used by a hypertable index
---

Since [0.2.0](https://github.com/timescale/timescaledb/releases/tag/0.2.0)

Get the disk space used by an index on a hypertable, including the disk space needed to provide the index on all chunks. The size is reported in bytes.

For more information about using hypertables, including chunk size partitioning, see the [hypertable section](/docs/learn/hypertables/understand-hypertables/index.md).

## Samples

Get size of a specific index on a hypertable.

```
\d conditions_table
                     Table "public.conditions_table"
 Column |           Type           | Collation | Nullable | Default
--------+--------------------------+-----------+----------+---------
 time   | timestamp with time zone |           | not null |
 device | integer                  |           |          |
 volume | integer                  |           |          |
Indexes:
    "second_index" btree ("time")
    "test_table_time_idx" btree ("time" DESC)
    "third_index" btree ("time")


SELECT hypertable_index_size('second_index');


 hypertable_index_size
-----------------------
                163840


SELECT pg_size_pretty(hypertable_index_size('second_index'));


 pg_size_pretty
----------------
 160 kB
```

## Arguments

The syntax is:

```
SELECT hypertable_index_size('<index_name>');
```

| Name         | Type     | Default | Required | Description                       |
| ------------ | -------- | ------- | -------- | --------------------------------- |
| `index_name` | REGCLASS | -       | ✔        | Name of the index on a hypertable |

## Returns

| Column                  | Type   | Description                              |
| ----------------------- | ------ | ---------------------------------------- |
| hypertable\_index\_size | BIGINT | Returns the disk space used by the index |

If the function is executed on a non-hypertable relation, `NULL` is returned.