How Are Immediate Change Fees Calculated?

Immediate Change Fee Formula

Immediate change fee = (New package price – Current package price) x Remaining package duration

Billing Example

Assume that you have purchased a one-month CodeArts Agent basic edition (US$20/month) on August 1, 2026, 00:00:00, and enabled auto-renewal. The system automatically completes the renewal on August 24, 2026, at 03:00, your billing cycle will be divided into the following two periods:

First billing period (initial validity period): August 1, 2026, 00:00:00 to August 31, 2026, 23:59:59

Second billing period (auto-renewal validity period): September 1, 2026, 00:00:00 to September 30, 2026, 23:59:59

If you initiate an immediate package change on August 25, 2026, 13:40:00 to upgrade to the "professional edition, 1 seat" (US$60/month), the immediate change fee is calculated as follows:

As shown in Figure 1, the immediate change fee is calculated in two time frames.

1. Remaining duration in August: 6 days and 10 hours from August 25, 13:40:00 to August 31, 23:59:59. Converted to months, this is approximately 0.20698925 months (6.41666667 days/31 days).
2. Remaining duration in September: one month (the entire September)

The final total fee for the immediate change is: (New package price – Current package price) x Remaining duration = (60 – 20) x (0.20698925 + 1) ≈ US$ 48.27.

• Remaining duration calculation rules: Upgrades initiated on the purchase date start from 00:00:00 the next day. Upgrades initiated after the purchase date start from the next full hour (or the current hour if upgraded exactly on the hour).

  Under these rules, the remaining duration for August in this example should be calculated starting from 2026-08-25, 14:00:00. For details on remaining duration calculation, see Pricing of Changed Specifications.

• The examples in this document are for reference only. The results in these examples are only calculated to two decimal places. When calculating the specification upgrade fee, you are advised to retain at least eight decimal places to ensure consistency between the results calculated and presented.

Figure 1 Example timeline for an immediate change