You can create your own custom fields so you can save information that’s unique to your business. But while you’re dreaming up all the ways you can customize your account with new fields, there are some space parameters to keep in mind. This limit isn’t based on a specific number of fields but rather the amount of space you have allotted to custom fields — roughly 39,600 bytes. Think of your field limit as the amount of space you have available on your “Ontraport hard drive.”
Every custom field you create uses up bytes, so the number of custom fields you can create depends on the types of fields you add. You could have thousands of checkbox fields that take up one byte each. Or you could have around 50 image fields that need 768 bytes a piece.
In this article you can find the number of bytes each custom field type requires. You’ll also learn how to estimate how much space you’re using and how to make more space for custom fields.
Table of Contents
Custom field types reference chart
Estimating your remaining space
Making space for custom fields
Custom field types reference chart
Below are the types of custom fields you can create and the number of bytes required for each:
Field Type | Bytes Required |
Address | 768 |
768 | |
Image | 768 |
Phone | 768 |
SMS | 768 |
State | 768 |
Text | 768 |
Rich Text | 255 |
URL | 255 |
Price | 64 |
Color | 20 |
Date | 20 |
Date and Time | 20 |
Dropdown | 20 |
List Selection | 20 |
Numeric | 20 |
Related Object Data | 11 |
Long Text | 8 |
Country | 5 |
Checkbox | 1 |
Estimating your remaining space
If you’d like to figure out how much space you have left for custom fields, you can estimate your data usage. Here’s how:
- Open a spreadsheet and list your custom field names and their data types in columns.
- Use the custom field types reference chart above to fill in a third column with the number of bytes required for each of your custom fields. Add up the total bytes with a formula or your favorite calculator.
- Subtract that number from 39,600, and you will get roughly how much space you have left.
- There is some overhead data usage per field, which is why this is an estimate instead of an exact number of bytes remaining.

Making space for custom fields
If you run out of space for custom fields, you can make more space by converting your text fields to long text fields. A normal text field takes up 768 bytes per field, but a long text only takes eight.
You won’t lose any data by converting because long text fields hold more characters. But there are a few things to keep in mind before you convert:
- We store long text fields in another database. This means that if you have a lot of long text fields, your records may take longer to load.
- After converting a text field to a long text field, you can view your saved data using Card View or in your records — not List View.
- The point of List View is to make important information easy to find, so you can only add fields you can read at a glance. Long text fields don’t fit because they can hold thousands of characters.
- Keep your fields as normal text fields if you want them to function as column headings, like this:
- You can’t convert long text fields back to text fields — this change will be permanent.

Convert your text fields to long text fields
- Hover over
and click Settings → Field Editor.
- If you want to convert text fields from other objects, hover over that object’s tab to get to your field editor.
- Select the custom text field you would like to convert.
- You can’t edit the default fields in your account, such as “City” or “IP Address.”
- Click the field type dropdown and select Long Text.
- Click
.
