Slate provides real-time and batched validation and standardization for United States and Canadian addresses that are submitted either interactively or non-interactively.
Address quality
If you create a query on the Address base, you’ll find you can filter for Quality. Behind the scenes, Slate gives addresses a quality score from 0 (the highest), to 3 (the lowest).

These scores correspond with each of the Quality filter values:
0 or Verified
Given to address records after validation.
1 or Skipped Validation
Address records given this ranking are not subject to the address standardization process, and they can be differentiated (for example, in a query) from addresses that have. Both methods described in this article bestow an Address - Quality value of 1.
2 or Missing Part of Address
Addresses without the Preserve Formatting option selected or without Unverified: Skip Validation set in static mapping receive an Address - Quality rank of 2. They are queued for overnight validation as part of the address standardization process.
3 or Potential Bad Address
Given to bad addresses, or those that can’t be validated.
Interactive validation and standardization
When an address is entered on a form, the address is validated and standardized immediately upon submission.
This validation and standardization happens interactively, meaning that, if the validator finds that the address is unverifiable or ambiguous, the user is prompted to make the requested corrections.
If the user ignores these recommendations, the submission continues without modification. An exception to this occurs when the address is ambiguous and the validator can provide additional standardization.
If the address is verifiable, the address is immediately standardized. For example, 123 Main Street becomes 123 Main St.
The standardization process corrects or fills in the street, city, state, and 9-digit postal codes. When standardized, the [quality] field on the [address] table will be set to 0, which corresponds with the address quality filter value Verified.
If the user elects to skip validation, this [quality] field is set to 1, which corresponds with the address quality filter value Skipped Validation.
Batch standardization
Addresses that come in through non-interactive sources, such as through uploaded datasets, receive a [quality] rating of 2, which corresponds with the address quality filter value Missing Part of Address, indicating the address awaits standardization.
Every evening, or on demand as initiated by an administrator in Database → Scrub Address Records, addresses with a [quality] of 2 will seek to be standardized. If they can be successfully standardized, their [quality] is updated to 0. If not, the [quality] is updated to 1.
Because addresses may not validate for a variety of reasons, the addresses are not marked explicitly as invalid (as designated with a [quality] rating of 3, or Potential Bad Address) as part of this batched process.