POST /forms/{slug}/answer HTTP/1.1
Host: api.opnform.com
Content-Type: application/json

{
"completion_time": 10,
"3700d380-197b-47b9-a008-3acc31bbd506": "Alice",
"12461db5-0c19-429e-840b-8de1e359c42f": "alice@example.com"
}

{
  "type": "success",
  "message": "Form submission saved.",
  "submission_id": "sub_1234567890",
  "is_first_submission": true,
  "redirect": false,
  "submission_hash": null
}

{
    "type": "success",
    "message": "Partial form submission saved.",
    "submission_hash": "hash_abc123def456"
}

{
    "message": "The Name field is required.",
    "errors": {
        "3700d380-197b-47b9-a008-3acc31bbd506": ["The Name field is required."],
        "12461db5-0c19-429e-840b-8de1e359c42f": [
            "The email field must be a valid email address."
        ]
    }
}

{
    "message": "Form not found.",
    "error": "The specified form slug does not exist or is not published."
}

POST

forms

{slug}

answer

POST /forms/{slug}/answer HTTP/1.1
Host: api.opnform.com
Content-Type: application/json

{
"completion_time": 10,
"3700d380-197b-47b9-a008-3acc31bbd506": "Alice",
"12461db5-0c19-429e-840b-8de1e359c42f": "alice@example.com"
}

{
  "type": "success",
  "message": "Form submission saved.",
  "submission_id": "sub_1234567890",
  "is_first_submission": true,
  "redirect": false,
  "submission_hash": null
}

{
    "type": "success",
    "message": "Partial form submission saved.",
    "submission_hash": "hash_abc123def456"
}

{
    "message": "The Name field is required.",
    "errors": {
        "3700d380-197b-47b9-a008-3acc31bbd506": ["The Name field is required."],
        "12461db5-0c19-429e-840b-8de1e359c42f": [
            "The email field must be a valid email address."
        ]
    }
}

{
    "message": "Form not found.",
    "error": "The specified form slug does not exist or is not published."
}

Create Form Submission

Submit a new response to a form using the OpnForm API. This endpoint allows you to programmatically collect form data without requiring user authentication.

This is a public endpoint designed for form submissions. No API authentication is required.

Prerequisites

Before submitting to a form, you’ll need:

A published form with a valid slug or UUID
Knowledge of the form’s field IDs (available via the Get Form endpoint)
Form fields configured according to your validation requirements

You can find your form’s slug in the OpnForm dashboard under form settings, or use the form’s UUID which is also displayed in the dashboard.

Request

POST /forms/{slug}/answer HTTP/1.1
Host: api.opnform.com
Content-Type: application/json

{
"completion_time": 10,
"3700d380-197b-47b9-a008-3acc31bbd506": "Alice",
"12461db5-0c19-429e-840b-8de1e359c42f": "alice@example.com"
}

Path Parameters

string

required

The form identifier - either a human-readable slug (e.g., customer-feedback) or UUID. You can find this in your OpnForm dashboard under form settings.

Request Body

string|number|boolean|array

Dynamic field data: Each form field is identified by its unique UUID. The value type depends on the field type:

Text fields: string
Number fields: number
Checkbox fields: boolean
Multi-select fields: array

Example: "3700d380-197b-47b9-a008-3acc31bbd506": "Alice Johnson"

number

Time in seconds it took the user to complete the form. Used for analytics and form optimization insights.

boolean

default:"false"

Submit the form as a partial submission. Only works if the form has “Collect partial submissions” enabled in its settings.When true, the response includes a submission_hash that can be used to update the same submission later.

Response

{
  "type": "success",
  "message": "Form submission saved.",
  "submission_id": "sub_1234567890",
  "is_first_submission": true,
  "redirect": false,
  "submission_hash": null
}

{
    "type": "success",
    "message": "Partial form submission saved.",
    "submission_hash": "hash_abc123def456"
}

{
    "message": "The Name field is required.",
    "errors": {
        "3700d380-197b-47b9-a008-3acc31bbd506": ["The Name field is required."],
        "12461db5-0c19-429e-840b-8de1e359c42f": [
            "The email field must be a valid email address."
        ]
    }
}

{
    "message": "Form not found.",
    "error": "The specified form slug does not exist or is not published."
}

Success Response Fields

string

Response type indicator. Always "success" for successful submissions.

string

Human-readable success message describing the submission result.

string|null

Unique identifier for the created submission. Returns null for partial submissions.

boolean

Indicates whether this is the first submission for this form. Useful for triggering welcome flows or first-time user experiences.

boolean

Indicates if the form has a custom redirect URL configured. Always false for API submissions.

string|null

Unique hash for partial submissions that can be used to update the submission later. Only present when is_partial: true.

Use Cases

Basic Form Submission

Submit a complete contact form with validation:

const submitContactForm = async (formData) => {
    try {
        const response = await fetch(
            "https://api.opnform.com/forms/contact-us/answer",
            {
                method: "POST",
                headers: { "Content-Type": "application/json" },
                body: JSON.stringify({
                    "3700d380-197b-47b9-a008-3acc31bbd506": formData.name,
                    "12461db5-0c19-429e-840b-8de1e359c42f": formData.email,
                    "a8f5c2d1-9b7e-4c3f-8a1d-2e5f9c4b7a8e": formData.message,
                    completion_time: formData.timeSpent,
                }),
            }
        );

        if (!response.ok) {
            throw new Error("Submission failed");
        }

        return await response.json();
    } catch (error) {
        console.error("Form submission error:", error);
        throw error;
    }
};

Partial Submission Workflow

Save progress and complete later:

// Save partial submission
const saveProgress = async (partialData) => {
    const response = await fetch(
        "https://api.opnform.com/forms/survey/answer",
        {
            method: "POST",
            headers: { "Content-Type": "application/json" },
            body: JSON.stringify({
                ...partialData,
                is_partial: true,
            }),
        }
    );

    const result = await response.json();
    // Store submission_hash for later use
    localStorage.setItem("submission_hash", result.submission_hash);
    return result;
};

// Complete the submission later
const completeSubmission = async (finalData) => {
    const hash = localStorage.getItem("submission_hash");
    const response = await fetch(
        "https://api.opnform.com/forms/survey/answer",
        {
            method: "POST",
            headers: { "Content-Type": "application/json" },
            body: JSON.stringify({
                ...finalData,
                submission_hash: hash,
                is_partial: false,
            }),
        }
    );

    return await response.json();
};

Path Parameters

slug

string

required

Body

application/json

completion_time

number

Time in seconds it took to complete the form

is_partial

boolean

If you want to submit your form as partial

Response

Form submission saved successfully

type

string

Example:

"success"

message

string

Example:

"Form submission saved."

submission_id

string | null

is_first_submission

boolean

redirect

boolean

Overview

Workspaces

Forms

Submissions

Integrations

Workspace Users

Zapier

Create Submission

Create Form Submission

Prerequisites

Request

Path Parameters

Request Body

Response

Success Response Fields

Use Cases

Basic Form Submission

Partial Submission Workflow

Path Parameters

Body

Response

​Create Form Submission

​Prerequisites

​Request

​Path Parameters

​Request Body

​Response

​Success Response Fields

​Use Cases

​Basic Form Submission

​Partial Submission Workflow

Path Parameters

Body

Response

Create Form Submission

Prerequisites

Request

Path Parameters

Request Body

Response

Success Response Fields

Use Cases

Basic Form Submission

Partial Submission Workflow