--- title: "Connect Paychex Flex to Hypamoon" description: "Paychex Flex documents its API, but access goes through Paychex Flex first. What it takes to connect it to Hypamoon, with sources." url: https://hypamoon.com/connect-to/paychex-flex --- 1. [Connect to](https://hypamoon.com/connect-to) 2. Paychex Flex HR, payroll and shifts # Connect Paychex Flex to Hypamoon Possible, with help from Paychex Flex. The API is documented, but you cannot just create a key: access goes through Paychex Flex first. Possible ## The check Three questions about the API of Paychex Flex, answered from its own docs. **Public API docs**\ **Yes.** [Read the docs](https://developer.paychex.com/resources/overview) **A key you create yourself**\ **No.** Access starts with a questionnaire for the Paychex partnerships team; after approval Paychex creates the application and issues a key and secret, and each client must approve the app in Paychex Flex. [developer.paychex.com](https://developer.paychex.com/partner) **Versions or a changelog**\ **Not confirmed.** The docs have a versioning section that could not be read. **How it signs in**\ OAuth 2.0 with a key and secret that Paychex issues to an approved application, combined with access granted by each client. **Webhooks**\ **Yes.** It can tell your app when something changes. [developer.paychex.com](https://developer.paychex.com/resources/overview) **Hosting**\ Cloud **Condition**\ API keys are only issued after an application to and approval by the Paychex partnerships team. ## What you can build Read workers and pay data for reporting, or send hours into payroll, once Paychex has approved the integration. Your chat writes it as a Hypamoon adapter from the docs above. Reading starts after you click Allow in the portal, and every write waits for your approval, one call at a time. [How adapters work](https://hypamoon.com/docs/adapters) ### Good to know - Paychex Flex signs in with OAuth or signed requests only, with tokens that expire. The Hypamoon vault holds a fixed key today, so an adapter for Paychex Flex takes more work: ask your chat to check this first. - Paychex asks for a demo of the finished integration before final approval. ## Try it in your chat First get access from Paychex Flex. Then fill in what to read and write, and send it. Say this in your chat > Build the Hypamoon recipe build-an-adapter for Paychex Flex. API docs: https://developer.paychex.com/resources/overview. Read: \[what\]. Write: \[what, or nothing\]. [Open in Claude](https://claude.ai/new?q=Build%20the%20Hypamoon%20recipe%20build-an-adapter%20for%20Paychex%20Flex.%20API%20docs%3A%20https%3A%2F%2Fdeveloper.paychex.com%2Fresources%2Foverview.%20Read%3A%20%5Bwhat%5D.%20Write%3A%20%5Bwhat%2C%20or%20nothing%5D.) In Claude, or another chat with the full Hypamoon connection; adapters are not in ChatGPT yet. You paste the key in the portal, never in the chat. [The full recipe](https://hypamoon.com/r/build-an-adapter) ## Sources Checked on 1 November 2026. - [developer.paychex.com/resources/overview](https://developer.paychex.com/resources/overview) - [developer.paychex.com/partner](https://developer.paychex.com/partner) Paychex Flex is a name of its owner, used here only to describe the software. This page is not an official integration and Hypamoon has no partnership with Paychex Flex. Found something that changed? Tell us at [support](https://hypamoon.com/support#contact). ## More in hr, payroll and shifts - [**ADP Workforce Now** Possible](https://hypamoon.com/connect-to/adp-workforce-now) - [**BambooHR** Open](https://hypamoon.com/connect-to/bamboohr) - [**Deel** Open](https://hypamoon.com/connect-to/deel) - [**Factorial** Open](https://hypamoon.com/connect-to/factorial) - [**Gusto** Possible](https://hypamoon.com/connect-to/gusto) - [**HiBob** Open](https://hypamoon.com/connect-to/hibob) - [**Loket.nl** Possible](https://hypamoon.com/connect-to/loket-nl) - [**Nmbrs** Open](https://hypamoon.com/connect-to/nmbrs) - [**Paylocity** Possible](https://hypamoon.com/connect-to/paylocity) - [**Personio** Open](https://hypamoon.com/connect-to/personio) - [**Planday** Open](https://hypamoon.com/connect-to/planday) - [**Remote** Open](https://hypamoon.com/connect-to/remote) - [**Rippling** Open](https://hypamoon.com/connect-to/rippling) - [**Shiftbase** Open](https://hypamoon.com/connect-to/shiftbase) - [**UKG Pro** Open](https://hypamoon.com/connect-to/ukg-pro) - [**Workday** Open](https://hypamoon.com/connect-to/workday) [All 267 tools](https://hypamoon.com/connect-to) ## Tool not listed? Ask the chat to check its API. The same three checks work for any software. Your chat reads the vendor's own docs and tells you what it found. Say this in your chat > Check if \[software\] has an open API that a Hypamoon adapter can use: public API docs, a key or token I can create myself without asking the vendor, and versions or a changelog. Link the pages you used. [Open in Claude](https://claude.ai/new?q=Check%20if%20%5Bsoftware%5D%20has%20an%20open%20API%20that%20a%20Hypamoon%20adapter%20can%20use%3A%20public%20API%20docs%2C%20a%20key%20or%20token%20I%20can%20create%20myself%20without%20asking%20the%20vendor%2C%20and%20versions%20or%20a%20changelog.%20Link%20the%20pages%20you%20used.) [Open in ChatGPT](https://chatgpt.com/?q=Check%20if%20%5Bsoftware%5D%20has%20an%20open%20API%20that%20a%20Hypamoon%20adapter%20can%20use%3A%20public%20API%20docs%2C%20a%20key%20or%20token%20I%20can%20create%20myself%20without%20asking%20the%20vendor%2C%20and%20versions%20or%20a%20changelog.%20Link%20the%20pages%20you%20used.) Fill in the name of your software. Checking needs no connection to Hypamoon. ## Ready to connect Paychex Flex? Connect your chat once, then ask it to build the adapter. [Start free](https://app.hypamoon.com/?mode=signup&utm_source=connect-to&utm_campaign=paychex-flex) Works in Claude and ChatGPT. [Add to Claude](https://hypamoon.com/connect?via=connect-to~paychex-flex#claude) [Add to ChatGPT](https://hypamoon.com/connect?via=connect-to~paychex-flex#chatgpt)