Billing rules and billable items of the pay-as-you-go billing method - Server Load Balancer

Classic Load Balancer (CLB) supports the pay-as-you-go billing method. Pay-as-you-go CLB instances support two metering methods: pay-by-LCU and pay-by-specification. You can release a pay-as-you-go instance anytime.

Note

Adjustments are made to the billable items of CLB. Beginning 00:00:00 (UTC+8), December 1, 2024, the following new billable items are used by pay-as-you-go CLB instances:
- Instance fee is renamed public IP retention fee.
- A billable item instance fee is added.
For more information, see CLB billing adjustments.
CLB provides high-performance instances and shared-resource instances. Shared-resource instances are no longer available for purchase. The CLB instances described in this topic refer to high-performance CLB instances.

Billing rules

Item	Description
Billing rules	The pay-as-you-go billing method allows you to use resources before you pay for the resources. Bills are generated and fees are deducted after each billing cycle.
Use scenarios	The pay-as-you-go billing method is ideal for the following scenarios: The resource usage fluctuates. The workloads expect temporary traffic spikes.
Billing cycles	Fees are calculated on an hourly basis (UTC+8). When the fees within a billing cycle are generated, a new billing cycle begins. If the usage duration is less than one hour within a billing cycle, the usage duration is rounded up to one hour. For example, if you create a pay-as-you-go CLB instance at 09:30:00 (UTC+8) and release the instance at 12:30:00 (UTC+8), you are charged for usage of four entire hours, from 09:00:00 (UTC+8) to 13:00:00 (UTC+8). Note If the total amount of the balance and vouchers in your Alibaba Cloud account is less than the fee that you need to pay, you are notified by text message or email.
Configuration changes	The following figure shows the metering methods and configuration changes of pay-as-you-go CLB instances. Pay-as-you-go CLB instances support the pay-by-LCU and pay-by-specification metering methods. You can switch between the metering methods. For more information, see Modify the configurations of a pay-as-you-go CLB instance. You can change the specification, Internet data transfer metering method, and maximum bandwidth of a pay-by-specification CLB instance.
Effective time of configuration changes	If you change the configuration of a CLB instance but do not change the metering method of Internet data transfer, the change immediately takes effect. If you change the configuration of a CLB instance and also change the metering method of Internet data transfer, the changes take effect at 00:00:00 (UTC+8) on the next day.
Bandwidth limits	Pay-by-data-transfer CLB instances: The maximum bandwidth is not a guaranteed value. It indicates the upper limit of bandwidth and is for reference only. In case of resource contention, the bandwidth allocated to each CLB instance may be lower than the maximum bandwidth value. Pay-by-bandwidth CLB instances: The maximum bandwidth is a guaranteed value. In scenarios where demand outstrips resource supplies, the bandwidth can reach the specified value. For more information, see Limits.

Metering methods

Pay-as-you-go CLB instances support the pay-by-LCU and pay-by-specification metering methods. The billable items of a CLB instance vary based on the metering method and network type of the CLB instance, and the metering method of Internet data transfer.

Note

In the following table, a hyphen (-) indicates that you are not charged the fee and a check mark (✔) indicates that you are charged the fee.

Pay-by-LCU (new)

Network type	Metering method of Internet data transfer	Performance	Instance fee	Public IP retention fee	Specification fee and LCU fee		Internet data transfer fee
Network type	Metering method of Internet data transfer	Performance	Instance fee	Public IP retention fee	Specification fee	LCU fee	Data transfer fee	Bandwidth fee
Internet-facing	Pay-by-data-transfer	Automatically scales on demand. The upper limit is defined in the s3.large specification.	✔	✔	-	✔	✔	-
Internal-facing	-	Automatically scales on demand. The upper limit is defined in the s3.large specification.	✔		-	✔	-	-

Pay-by-specification

Instance network type	Metering method of Internet data transfer	Instance performance limit	Instance fee	Public IP retention fee	Specification & LCU fee		Internet data transfer fee
Instance network type	Metering method of Internet data transfer	Instance performance limit	Instance fee	Public IP retention fee	Specification fee	LCU fee	Data transfer fee	Bandwidth fee
Public network	Pay-by-traffic	Determined by the purchased specification, with a maximum option of s3.large	✔	✔	✔	-	✔	-
Public network	Pay-by-bandwidth	Determined by the purchased specification, with a maximum option of s3.large	✔	✔	✔	-	-	✔
Private network	-	Determined by the purchased specification, with a maximum option of s3.large	✔		✔	-	-	-

You can use the CLB LCU Calculator to estimate the number of LCUs consumed by your CLB instance.

Instance fee

You are charged instance fees for CLB instances on an hourly basis. If the usage duration in a billing cycle is less than one hour, the usage duration is rounded up to one hour. The usage duration refers to the period of time from when a CLB instance is created to when the CLB instance is released.

Instance fee = Instance unit price (USD/hour) × Duration of usage (hours), where the instance unit price is "USD 0.021 per hour".

Note

CLB instances created before December 1, 2024, 00:00:00 (UTC+8) are temporarily exempt from instance fees and are free of charge until November 30, 2025, 23:59:59 (UTC+8). For more information, see CLB billing adjustments.

Public IP retention fee

You are charged a public IP retention fee based on the unit price of the public IP address and the duration of your usage.

Public IP retention fee = Unit price of public IP address × Duration of usage × Number of instances

Click to view the regions and unit prices. The prices in the following table are for reference only. The prices on the buy page shall prevail.

Region	Instance fee (USD/hour)
China (Hangzhou), China (Shanghai), China (Qingdao), China (Beijing), China (Zhangjiakou), China (Hohhot), China (Shenzhen), China (Heyuan), and China (Chengdu)	0.003
China (Hong Kong), Japan (Tokyo), UAE (Dubai), and South Korea (Seoul)	0.009
US (Silicon Valley) and US (Virginia)	0.005
Singapore, Malaysia (Kuala Lumpur), Indonesia (Jakarta), UK (London), Germany (Frankfurt), and Thailand (Bangkok)	0.006

Specification fee and LCU fee

Specification fee

You are charged specification fees only for pay-by-specification CLB instances. The following section describes the key metrics of high-performance CLB instances. The performance of a CLB instance varies based on the specification. For more information, see FAQ about CLB instances.

Maximum number of connections: The maximum number of connections that can be established to a CLB instance. When the number of existing concurrent connections reaches the upper limit, new connection requests are dropped.
Connections per second (CPS): The maximum number of new connections that can be established to a CLB instance per second. When the actual number reaches the upper limit, new connection requests are denied.
Queries per second (QPS): The maximum number of HTTP or HTTPS requests that can be processed per second. This metric is specific to Layer 7 listeners. When the actual number reaches the upper limit, new requests are denied.

Click to view the specifications, performance metrics, and prices. The prices in the following table are for reference only. The prices on the buy page shall prevail.

Specification	Maximum number of connections	CPS	QPS	Unit price in the Chinese mainland and China (Hong Kong) (USD/hour)	Unit price outside China (USD/hour)
Specification 1: Small I (slb.s1.small)	5,000	3,000	1,000	0.01	0.012
Specification 2: Medium I (slb.s2.small)	50,000	5,000	5,000	0.05	0.06
Specification 3: Medium II (slb.s2.medium)	100,000	10,000	10,000	0.10	0.12
Specification 4: Large I (slb.s3.small)	200,000	20,000	20,000	0.20	0.24
Specification 5: Large II (slb.s3.medium)	500,000	50,000	30,000	0.31	0.37
Specification 6: Super Large I (slb.s3.large)	1,000,000	100,000	50,000	0.51	0.61

Example: Alice purchased an Internet-facing CLB instance of the slb.s2.small specification at 10:00:00 (UTC+8) on November 20, 2021 in the China (Hangzhou) region and released the CLB instance at 12:34:00 (UTC+8) on November 21, 2021. The specification fee is calculated based on the following formula:

Unit price of the slb.s2.small specification in the China (Hangzhou) region = USD 0.05 per hour
Usage duration = 27 hours
Specification fee = USD 0.05 per hour × 27 hours = USD 1.35

LCU fee

A Load Balancer Capacity Unit (LCU) is the smallest unit that is used to measure resources consumed by CLB instances.

Definition

You are charged LCU fees of CLB on an hourly basis. The billing cycle is one hour. If the usage duration in a billing cycle is less than 1 hour, the usage duration is rounded up to one hour.

LCU fee per hour = LCU unit price (USD per LCU) × Number of LCUs consumed per hour

Number of LCUs per hour = max {Number of LCUs consumed by new connections, Number of LCUs consumed by concurrent connections, Number of LCUs consumed by data transfer, Number of LCUs consumed by rule evaluations}

LCUs are used to measure the performance when CLB processes traffic. The performance metrics of an LCU vary based on the protocol of the CLB listener.

TCP traffic

Metric	Description	Unit	LCU coefficient	Calculation
Number of new connections	The number of new TCP connections processed per second.	Seconds	800	The system collects all CPS values within a billing cycle and then divides the largest CPS value by the LCU coefficient to calculate the number of LCUs. The number of LCUs is calculated based on the following formula: `Number of LCUs = Largest CPS value/LCU coefficient`
Number of concurrent connections (CONNS)	The number of concurrent TCP connections per minute.	Minutes	100,000	The system collects all CONNS values within a billing cycle and then divides the largest CONNS value by the LCU coefficient to calculate the number of LCUs. The number of LCUs is calculated based on the following formula: `Number of LCUs = Largest CONNS value/LCU coefficient`
Amount of data transfer	The amount of data transfer over TCP that is processed by CLB. Unit: GB.	Hours	1 GB	The system divides the total amount of data transfer over TCP within a billing cycle by the LCU coefficient to calculate the number of LCUs. The number of LCUs is calculated based on the following formula: `Number of LCUs = Total amount of data transfer/LCU coefficient`

UDP traffic

Metric	Description	Unit	LCU coefficient	Calculation
Number of new connections	The number of new UDP connections processed per second.	Seconds	400	The system collects all CPS values within a billing cycle and then divides the largest CPS value by the LCU coefficient to calculate the number of LCUs. The number of LCUs is calculated based on the following formula: `Number of LCUs = Largest CPS value/LCU coefficient`
Number of CONNS	The number of concurrent UDP connections per minute.	Minutes	50,000	The system collects all CONNS values within a billing cycle and then divides the largest CONNS value by the LCU coefficient to calculate the number of LCUs. The number of LCUs is calculated based on the following formula: `Number of LCUs = Largest CONNS value/LCU coefficient`
Amount of data transfer	The amount of data transfer over UDP that is processed by CLB. Unit: GB.	Hours	1 GB	The system divides the total amount of data transfer over UDP within a billing cycle by the LCU coefficient to calculate the number of LCUs. The number of LCUs is calculated based on the following formula: `Number of LCUs = Total amount of data transfer/LCU coefficient`

HTTP and HTTPS traffic

Metric	Description	Unit	LCU coefficient	Calculation
Number of new connections	The number of new HTTP and HTTPS connections processed per second.	Seconds	25	The system collects all CPS values within a billing cycle and then divides the largest CPS value by the LCU coefficient to calculate the number of LCUs. The number of LCUs is calculated based on the following formula: `Number of LCUs = Largest CPS value/LCU coefficient`
Number of CONNS	The number of concurrent HTTP and HTTPS connections per minute.	Minutes	3,000	The system collects all CONNS values within a billing cycle and then divides the largest CONNS value by the LCU coefficient to calculate the number of LCUs. The number of LCUs is calculated based on the following formula: `Number of LCUs = Largest CONNS value/LCU coefficient`
Amount of data transfer	The data transfer over HTTP and HTTPS that is processed by CLB. Unit: GB.	Hours	1 GB	The system divides the total amount of data transfer over HTTP and HTTPS within a billing cycle by the LCU coefficient to calculate the number of LCUs. The number of LCUs is calculated based on the following formula: `Number of LCUs = Total amount of data transfer/LCU coefficient`
Number of rule evaluations	The product of the number of forwarding rules processed by CLB and the number of queries per second (QPS). The first 25 forwarding rules are free of charge. If the number of forwarding rules processed by CLB is greater than 25, the following formula applies: Number of rule evaluations = QPS × (Number of forwarding rules processed by CLB - 25). If the number of forwarding rules is less than 25, the following formula applies: Number of rule evaluations = QPS.		1,000	The system collects the number of forwarding rules and all QPS values within a billing cycle and uses the largest QPS value to calculate the number of rule evaluations. Then, the system divides the number of rule evaluations by the LCU coefficient to calculate the number of LCUs. The number of LCUs is calculated based on the following formula: `Number of LCUs = Number of rule evaluations/LCU coefficient`

The number of LCUs that are consumed by a CLB listener per hour is equal to the largest number of LCUs consumed for different metrics. The LCU fee of a CLB instance is the sum of the LCU fees for all listeners.

LCU unit price

The unit price of LCUs is "USD 0.007 per LCU-hour". The prices on the purchase page shall prevail.

After the hourly metrics of a CLB instance are converted into LCUs, the hourly LCU consumption is calculated based on the actual usage. The LCU consumption is accurate to 0.000001 LCU. For example, if you consume 0.1 LCU in an hour, the LCU fee for the hour is calculated based on this formula: 0.1 × 0.007 = USD 0.0007.

Billing examples

Alice created a pay-by-LCU CLB instance in the China (Hangzhou) region at 08:10:00 (UTC+8) on June 8, 2022, and configured a TCP listener and an HTTP listener for the instance. Alice released the instance at 08:50:00 (UTC+8) on June 8, 2022. The following table describes the largest CPS value, the largest CONNS value, the amount of data transfer, and the largest number of rule evaluations of the CLB instance from 08:10:00 (UTC+8) to 08:50:00 (UTC+8).

Metric	TCP	HTTP
CPS per second	The largest CPS value within the hour is 1,600. The number of LCUs is calculated based on the following formula: `1,600÷800=2`	The largest CPS value within the hour is 100. The number of LCUs is calculated based on the following formula: `100÷25=4`
CONNS per minute	The largest CONNS value within the hour is 480,000. The number of LCUs is calculated based on the following formula: `480,000÷100,000=4.8`	The largest CONNS value within the hour is 12,000. The number of LCUs is calculated based on the following formula: `12,000÷3,000=4`
Data transfer per hour	The data transfer over TCP processed by CLB within the hour is 4 GB. The number of LCUs is calculated based on the following formula: `4÷1=4`	The data transfer over HTTP processed by CLB within the hour is 3.6 GB. The number of LCUs is calculated based on the following formula: `3.6÷1=3.6`
Number of rule evaluations per second	0	For example, 40 forwarding rules are created for the HTTP listener, and the highest QPS value within the hour is 400. In this example, the number of forwarding rules that you configured exceeds the free quota. The largest number of rule evaluations within the hour is calculated based on the following formula: `(40-25)×400=6,000` The number of LCUs is calculated based on the following formula: `6,000÷1,000=6`

In this example, the metric for which the TCP listener consumes the largest number of LCUs is the number of concurrent connections (4.8 LCUs), and the metric for which the HTTP listener consumes the largest number of LCUs is the number of rule evaluations (6 LCUs).

LCU fee for the TCP listener = USD 0.007 × 4.8 = USD 0.0336
LCU fee for the HTTP listener = USD 0.007 × 6 = USD 0.042
Hourly LCU fee for the CLB instance = LCU fee for the TCP listener + LCU fee for the HTTP listener = USD 0.0336 + USD 0.042 = USD 0.0756
The average monthly LCU fee for the CLB instance is calculated based on the following formula: USD 0.0756 × 24 × 30 = USD 54.432

Estimate LCU consumption

You can use the CLB LCU Calculator to estimate the number of LCUs consumed by your CLB instance.

Internet data transfer fee

Data transfer fee (charged for pay-by-data-transfer Internet-facing instances)

You are charged for outbound data transfer over the Internet. You are not charged for inbound data transfer over the Internet. You are charged and billed for pay-by-data-transfer Internet-facing CLB instances on an hourly basis. If the usage duration is less than 1 hour in a billing cycle, the usage duration is rounded up to 1 hour.

Data transfer fee = Unit price of data transfer (USD/GB) × Amount of data transfer (GB)

Click to view data transfer unit prices. The region-specific prices in the following table are for reference only. The prices on the buy page shall prevail.

Region	Data transfer fee (USD/GB)
China (Hangzhou), China (Shanghai), China (Beijing), China (Zhangjiakou), China (Hohhot), China (Shenzhen), and China (Heyuan)	0.125
China (Qingdao)	0.113
China(Hong Kong)	0.156
US (Silicon Valley) and US (Virginia)	0.078
Malaysia (Kuala Lumpur)	0.112
Singapore, Indonesia (Jakarta), and Thailand (Bangkok)	0.117
Japan (Tokyo)	0.087
Germany (Frankfurt) and UK (London)	0.070
UAE (Dubai)	0.447
South Korea (Seoul)	0.123

Example: Alice purchased an Internet-facing pay-by-data-transfer CLB instance at 10:00:00 (UTC+8) on November 20, 2021 in the China (Hangzhou) region and released the CLB instance at 12:34:00 (UTC+8) on November 21, 2021. The outbound data transfer over the Internet is 5 GB.

Unit price of data transfer in the China (Hangzhou) region = USD 0.125 per GB
Outbound data transfer: 5 GB
Data transfer fee = USD 0.125 per GB × 5 GB = USD 0.625

Bandwidth fee (charged for pay-by-bandwidth Internet-facing instances)

You are charged and billed for pay-by-bandwidth Internet-facing CLB instances on a daily basis. If the usage duration in a billing cycle is less than one hour, the usage duration is rounded up to one hour. If the usage duration is less than one day, you are charged based on the number of hours that you use a CLB instance. The usage duration is the duration for which a CLB instance uses bandwidth.

The bandwidth fee of a pay-by-bandwidth Internet-facing CLB instance is calculated based on a tiered pricing model with 5 Mbit/s as the standard bandwidth value.
If you modified the maximum bandwidth of a CLB instance within a billing cycle, you are charged based on the highest value on that day.

Note

For pay-by-bandwidth CLB instances, the maximum inbound bandwidth is the same as the maximum outbound bandwidth.

For a CLB instance whose maximum bandwidth is from 1 to 5 Mbit/s, the bandwidth fee is calculated by using the following formula: Bandwidth fee = Maximum bandwidth × Bandwidth unit price × Usage duration.
For a CLB instance whose maximum bandwidth is higher than 5 Mbit/s, the bandwidth fee is calculated by using the following formula: Bandwidth fee = [5 × Unit price of bandwidth from 1 to 5 Mbit/s + (Maximum bandwidth - 5) × Unit price of bandwidth higher than 5 Mbit/s] × Usage duration.

Click to view bandwidth unit prices. The region-specific prices in the following table are for reference only. The prices on the buy page shall prevail.

Region	Bandwidth fee for 1 to 5 Mbit/s (USD/hour)	Fee for bandwidth between 1 and 5 Mbit/s (USD/day)	Fee for bandwidth higher than 5 Mbit/s (USD/hour)	Fee for bandwidth higher than 5 Mbit/s (USD/day)
China (Hangzhou), China (Shanghai), China (Beijing), China (Zhangjiakou), China (Hohhot), China (Shenzhen), China (Heyuan), and China (Chengdu)	0.006	0.144	0.02	0.48
China (Qingdao)	0.005	0.12	0.016	0.384
China (Hong Kong)	0.006	0.144	0.02	0.48
Singapore, Indonesia (Jakarta), Malaysia (Kuala Lumpur), Germany (Frankfurt), UK (London), Thailand (Bangkok), and South Korea (Seoul)	0.006	0.144	0.02	0.48
Japan (Tokyo)	0.007	0.168	0.023	0.552
UAE (Dubai)	0.048	11.52	0.118	2.832
US (Silicon Valley) and US (Virginia)	0.006	0.144	0.02	0.48

Example: Alice purchased an Internet-facing CLB instance whose maximum bandwidth is 2 Mbit/s in the China (Hangzhou) region at 10:00:00 (UTC+8) on November 20, 2021 and changed the maximum bandwidth to 20 Mbit/s at 08:00:00 (UTC+8) on November 21, 2022. Then, Alice released the CLB instance at 12:34:00 (UTC+8) on November 21, 2022. The bandwidth fee is calculated based on the following formula:

Maximum bandwidth on the day when Alice purchased the CLB instance: 2 Mbit/s
Maximum bandwidth on the day when Alice modified the maximum bandwidth of the CLB instance: 20 Mbit/s
Bandwidth fee for the first day: (2 × 0.006) × 14 = USD 0.168
Bandwidth fee for the next day: [5 × 0.006 + (20 - 5) × 0.02] × 13 = USD 4.29
Total fee = 0.168 + 4.29 = USD 4.458