# Show Base64 offsets

When a string is within a block of data and the whole block is Base64'd, the string itself could be represented in Base64 in three distinct ways depending on its offset within the block. This operation shows all possible offsets for a given string so that each possible encoding can be considered. Show Base64 offsets lives in the **Data format** category of the `fx` menu.

## Parameters

| Parameter                       | Type    | Required | Default        | Description                                            |
| ------------------------------- | ------- | -------- | -------------- | ------------------------------------------------------ |
| Input                           | string  | yes      | —              | Value to transform. Previous step output or a literal. |
| Alphabet                        | string  | no       | `A-Za-z0-9+/=` | Argument value for this operation.                     |
| Show variable chars and padding | boolean | no       | `true`         | Enabled by default.                                    |
| Input format                    | string  | no       | `Raw`          | Choose one of: `Raw`, `Base64`.                        |

`Input` is the primary value (previous step output or a literal).

## Returned value

| Type   | Description                                       |
| ------ | ------------------------------------------------- |
| `html` | Result of the Show Base64 offsets transformation. |

## Limitations

- This operation treats Input as raw bytes (binary-capable). Non-text payloads may display differently after decoding.
- Invalid or mismatched encoding for the chosen options typically raises an evaluation error — fix the Input or options before re-running.

## Example

<details>
<summary>Run Show Base64 offsets</summary>

When a string is within a block of data and the whole block is Base64'd, the string itself could be represented in Base64 in three distinct ways depending on its offset within the block. Adjust optional parameters when the defaults do not match your payload.

1. Set **Input** to the value to transform (previous step output or a literal).

2. Review **Alphabet**, **Show variable chars and padding**, **Input format** and keep defaults unless your format requires otherwise.

3. Confirm **Output value** shows the transformed result.

</details>