---
title: Bundle methodologies · Cloudflare SSL/TLS docs
description: When an SSL certificate is deployed to Cloudflare's global network, it may be augmented with intermediate and root certificates to assist the user agent in finding a chain to a publicly trusted root.
lastUpdated: 2025-04-07T10:50:11.000Z
source_url:
  html: https://a74404c8.preview.developers.cloudflare.com/ssl/edge-certificates/custom-certificates/bundling-methodologies/index.md
  md: https://a74404c8.preview.developers.cloudflare.com/ssl/edge-certificates/custom-certificates/bundling-methodologies/
---

When an SSL certificate is deployed to Cloudflare's global network, it may be augmented with intermediate and root certificates to assist the user agent in finding a chain to a publicly trusted root.

You can control the mechanics of how certificates are bundled by specifying a bundling methodology.

## Intermediate and root certificates

Cloudflare maintains intermediate and root certificates used for bundling on a [GitHub repository](https://github.com/cloudflare/cfssl_trust). As the certificates expire or are removed by certificate authorities, Cloudflare removes and adds them accordingly.

Expiration values for these certificates may appear in the `expires_on` field when you use the [Analyze Certificate endpoint](https://developers.cloudflare.com/api/resources/ssl/subresources/analyze/methods/create/) - often when the methodology you specify is [Compatible](#compatible). However, these expiration values reflect intermediate and root certificates - which are handled by Cloudflare -, not the leaf certificate you would have previously uploaded to Cloudflare.

## Methodologies

### Compatible

Compatible is the default methodology and uses **common and well distributed intermediate certificates** to complete the chain. This ensures that the resulting bundle is compatible with as many clients as possible. The related value for the `bundle_method` parameter when using the [API](https://developers.cloudflare.com/api/resources/custom_certificates/methods/create/) is `ubiquitous`.

### Modern

Modern consists of attempts to make the chain as efficient as possible, often by using **newer or fewer intermediate certificates**. The related value for the `bundle_method` parameter when using the [API](https://developers.cloudflare.com/api/resources/custom_certificates/methods/create/) is `optimal`.

### User-defined

User-defined allows you to paste **your own certificate chain** and present that bundle to clients. You must specify any intermediates you wish to use, followed by the leaf. If you are using a self-signed certificate (not recommended), you must use this mode. The related value for the `bundle_method` parameter when using the [API](https://developers.cloudflare.com/api/resources/custom_certificates/methods/create/) is `force`.
