US W9 OCR Ruby

The Ruby OCR SDK supports the W9 API.

Using the sample below, we are going to illustrate how to extract the data that we want using the OCR SDK.
W9 sample


require 'mindee'

# Init a new client
mindee_client = 'my-api-key')

# Load a file from disk
input_source = mindee_client.source_from_path('/path/to/the/file.ext')

# Parse the file
result = mindee_client.parse(

# Print a full summary of the parsed data in RST format
puts result.document

Output (RST):

:Mindee ID: d7c5b25f-e0d3-4491-af54-6183afa1aaab
:Filename: default_sample.jpg

:Product: mindee/us_w9 v1.0
:Rotation applied: Yes


Page Predictions

Page 0
:Name: Stephen W Hawking
:SSN: 560758145
:Address: Somewhere In Milky Way
:City State Zip: Probably Still At Cambridge P O Box CB1
:Business Name:
:EIN: 942203664
:Tax Classification: individual
:Tax Classification Other Details:
:W9 Revision Date: august 2013
:Signature Position: Polygon with 4 points.
:Signature Date Position:
:Tax Classification LLC:

Field Types

Standard Fields

These fields are generic and used in several products.

Basic Field

Each prediction object contains a set of fields that inherit from the generic Field class.
A typical Field object will have the following attributes:

  • value (String, Float, Integer, Boolean): corresponds to the field value. Can be nil if no value was extracted.
  • confidence (Float, nil): the confidence score of the field prediction.
  • bounding_box (Mindee::Geometry::Quadrilateral, nil): contains exactly 4 relative vertices (points) coordinates of a right rectangle containing the field in the document.
  • polygon (Mindee::Geometry::Polygon, nil): contains the relative vertices coordinates (Point) of a polygon containing the field in the image.
  • page_id (Integer, nil): the ID of the page, is nil when at document-level.
  • reconstructed (Boolean): indicates whether an object was reconstructed (not extracted as the API gave it).

Aside from the previous attributes, all basic fields have access to a to_s method that can be used to print their value as a string.

Position Field

The position field PositionField does not implement all the basic Field attributes, only bounding_box, polygon and page_id. On top of these, it has access to:

  • rectangle (Mindee::Geometry::Quadrilateral): a Polygon with four points that may be oriented (even beyond canvas).
  • quadrangle (Mindee::Geometry::Quadrilateral): a free polygon made up of four points.

String Field

The text field StringField only has one constraint: it's value is a String (or nil).

Page-Level Fields

Some fields are constrained to the page level, and so will not be retrievable to through the document.


The following fields are extracted for W9 V1:


πŸ“„address (StringField): The street address (number, street, and apt. or suite no.) of the applicant.

for address_elem in result.document.address do
  puts address_elem.value

Business Name

πŸ“„business_name (StringField): The business name or disregarded entity name, if different from Name.

for business_name_elem in result.document.business_name do
  puts business_name_elem.value

City State Zip

πŸ“„city_state_zip (StringField): The city, state, and ZIP code of the applicant.

for city_state_zip_elem in result.document.city_state_zip do
  puts city_state_zip_elem.value


πŸ“„ein (StringField): The employer identification number.

for ein_elem in result.document.ein do
  puts ein_elem.value


πŸ“„name (StringField): Name as shown on the applicant's income tax return.

for name_elem in do
  puts name_elem.value

Signature Date Position

πŸ“„signature_date_position (PositionField): Position of the signature date on the document.

for signature_date_position_elem in result.document.signature_date_position do
  puts signature_date_position_elem.polygon

Signature Position

πŸ“„signature_position (PositionField): Position of the signature on the document.

for signature_position_elem in result.document.signature_position do
  puts signature_position_elem.polygon


πŸ“„ssn (StringField): The applicant's social security number.

for ssn_elem in result.document.ssn do
  puts ssn_elem.value

Tax Classification

πŸ“„tax_classification (StringField): The federal tax classification, which can vary depending on the revision date.

for tax_classification_elem in result.document.tax_classification do
  puts tax_classification_elem.value

Tax Classification LLC

πŸ“„tax_classification_llc (StringField): Depending on revision year, among S, C, P or D for Limited Liability Company Classification.

for tax_classification_llc_elem in result.document.tax_classification_llc do
  puts tax_classification_llc_elem.value

Tax Classification Other Details

πŸ“„tax_classification_other_details (StringField): Tax Classification Other Details.

for tax_classification_other_details_elem in result.document.tax_classification_other_details do
  puts tax_classification_other_details_elem.value

W9 Revision Date

πŸ“„w9_revision_date (StringField): The Revision month and year of the W9 form.

for w9_revision_date_elem in result.document.w9_revision_date do
  puts w9_revision_date_elem.value


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