Simplicate API: connect Simplicate to your accounts, website and HR

What you can do with the Simplicate API

• Website forms as a lead or organisation in Simplicate
• Invoices from Simplicate to your accounts
• Fetch hours and projects for reporting and dashboards
• Keep employees, leave and absence in sync with HR or payroll
• Keep contact persons and organisations in sync with your mailing list

How the integration works

In Simplicate you create an API token under the general settings; the permissions follow the user the token was created for. The integration uses the REST API v2 and, where it exists, the newer v3. Simplicate sends signed webhooks on events such as a new invoice or a changed organisation; the integration checks the signature and then fetches the current data. Simplicate guarantees at least 60 calls per minute, so the integration works in batches.

Facts about the Simplicate API

Checked on 2 November 2026 against the official documentation. Limits, prices and versions change; the source is listed per row.

Fact	What the documentation says	Source
Authentication	API token (key and secret) created in Simplicate under the general settings; the permissions are those of the user the token was created for. v2 through two headers, v3 as Bearer.	Simplicate: Getting started v2
Token lifetime	No expiry described; the token works until it is deleted.	Simplicate: Getting started v2
Rate limits	At least 60 calls per minute; Simplicate may adjust the limit per endpoint. When exceeded, 429.	Simplicate: Getting started v2
Webhooks	Yes, configurable per event (projects, hours, invoices, organisations, persons and more), with an HMAC-SHA256 signature in X-Webhook-Signature. The secret is only visible when created.	Simplicate: Webhooks
Test environment	Not in the official documentation.	Simplicate: Developer
Version	API v2 (REST) and the newer v3 with a limited number of endpoints, usable side by side; no deprecation of v2 announced.	Simplicate: Getting started v3
API cost	Not in the official documentation.	Simplicate: Developer
n8n	No built-in node and no community node found; the integration runs through an HTTP step in n8n.	n8n documentation

What you need on your side

• A Simplicate administrator who can create a separate user with limited permissions and an API token
• A fixed source value per form or channel
• The ledger and VAT mapping of invoices, aligned with your accountant
• Access to the accounts, HR or mailing list on the other side

Where it often goes wrong, and how I prevent it

• Too broad permissions: an API token inherits a user's permissions. I create a separate user with only the permissions the integration needs.
• Lost webhook secret: a webhook's secret is only visible when it is created. The integration stores it securely straight away.
• Minute limit: above 60 calls per minute Simplicate may return a 429. The integration spreads the work.
• Invoice to accounts: ledger and VAT of a Simplicate invoice must match your accounts. I record that up front.

In practice

A Simplicate integration is not yet listed as In production with me. The approach is the same as for Zoho CRM: one source for origin, a fixed key per organisation, webhooks as the signal and the API as the source, and a notification when something does not arrive.

What it costs

I build a Simplicate integration as one scoped process for a fixed price, from €750. Maintenance and monitoring are a monthly fee: n8n management from €250 per month, server management €145 per server. In the free assessment we work out your process. All prices and what is included →

What I do not do

• I do not configure Simplicate itself (workflows, templates, roles); I connect to it.
• I do not use an administrator's API token when a user with limited permissions is enough.
• I do not trust a webhook blindly; the integration checks the signature and fetches the current data.

Frequently asked questions about the Simplicate API

Does n8n have a Simplicate node?

No, and no community node was found either. I connect Simplicate through the official API with an HTTP step in n8n.

How do I get access to the Simplicate API?

In Simplicate you create an API token (key and secret) under the general settings. That token's permissions are those of the user it was created for, so I ask for a separate user with limited permissions.

How many calls per minute does Simplicate allow?

Simplicate guarantees at least 60 per minute and may adjust the limit per endpoint. Above that Simplicate returns a 429. The integration therefore works in batches.

Can Simplicate notify the integration?

Yes. Simplicate has webhooks for projects, hours, invoices, organisations, persons and more, with a signature the integration checks. On a 429 Simplicate retries up to three times.

Is there a test environment?

Not according to the documentation. I therefore test with clearly marked test records that are cleaned up afterwards, or on a separate Simplicate environment if you have one.