To keep a target amount after a payment-processing fee, invoice (desired net + fixed fee) ÷ (1 − percentage fee rate). The percentage applies to the full amount charged, so the formula accounts for the fee being taken from the gross—not just from your target net.
Use this formula to calculate the gross invoice amount
For a transaction charged at one percentage rate plus one fixed fee:
As an Amazon Associate I earn from qualifying purchases.
Gross invoice amount = (desired net amount + fixed fee) ÷ (1 − percentage fee rate)
Free tools Windows power users keep installed
One-click scans. No signup required.
Use the percentage as a decimal: for example, 2.9% becomes 0.029. Let N be the amount you want to keep, r the percentage rate, f the fixed fee in the same currency, and G the amount charged. The fee is rG + f, so the amount remaining is G − (rG + f). Setting that equal to N and solving gives G = (N + f) ÷ (1 − r).
#1 Best Overall
- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
- Compact & Travel-Friendly: The ultra-compact design allows the adapter to stay plugged into your device without blocking adjacent ports or adding bulk, reducing wear and tear on your original USB ports.
- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
This is an algebraic calculation for a fee made up of a percentage of the gross and a fixed amount; it is not a formula quoted from either processor’s pricing page.
Worked example: invoice $103.30 to target $100 after Stripe’s US standard card fee
Stripe’s US pricing page lists standard online domestic card processing at 2.9% + $0.30 per successful transaction. The page was checked on October 8, 2026. For a $100 target before other costs:
Rank #2
- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
- Quick Data Transfers: Accelerate your productivity with rapid data transfers using a high-speed 5Gbps USB 3.0 port and two 480Mbps USB 2.0 ports.
- 4K HDMI Display: Enhance your visual experience with a hub capable of delivering 4K resolution at 30Hz in both mirror and extend modes. Please note that this hub is compatible with MacBook (macOS 12 and newer), Windows 10 and 11, ChromeOS, and laptops equipped with DP Alt Mode and Power Delivery. Note: This device is not compatible with Linux.
- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
- Convert 2.9% to a decimal:
0.029. - Substitute the target and fee:
($100 + $0.30) ÷ (1 − 0.029) = $103.2966…. - Round up to the next cent-denominated invoice amount: $103.30.
- Recalculate the estimated fee and net using the applicable processor fee calculation and rounding rules.
The calculation gives a practical cents-level starting amount, not a guarantee of an exact settlement to the cent. Stripe lists additional charges for some circumstances, including manually entered or international cards and currency conversion. Use the rate and any modifiers that apply to the actual transaction, rather than assuming the standard domestic-card rate.
How to apply the formula to PayPal
PayPal does not have one universal merchant fee rate. Its US merchant-fees page breaks fees out by product and payment type, defines domestic and international transactions, and notes that an additional percentage-based fee may apply to relevant international transactions. The page states that it was last updated September 1, 2026.
Rank #3
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
- Find the fee row for the PayPal product and payment type the customer will use.
- Confirm the seller’s country, transaction geography, and payment currency match the row and any applicable surcharge conditions.
- Take the percentage and fixed fee from that schedule, keeping the fixed fee in the same currency as the desired net.
- Substitute those values into
(N + f) ÷ (1 − r), then round to the invoice currency’s smallest unit and recheck the estimated net.
For an actual invoice, verify the current account-specific schedule. Rates may depend on country, currency, payment method, transaction circumstances, account eligibility, or negotiated terms.
When the simple reverse-fee formula does not fit
The equation works only when the applicable fee can be represented as one percentage of the gross plus a fixed amount. Include all applicable components only when the processor’s terms establish that they apply to the same transaction base.
Rank #4
- Dual Converters, Infinite Potential：Includes 2× USB C male to USB A female adapters and 2× USB A male to USB C female adapters. Perfect for a wide range of uses—tablets with Bluetooth keyboards, expand USB ports on macbook, and more. Two different converters for all your daily needs
- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
- Upgraded Exquisite Craftsmanship: With an aluminum alloy housing and metal connector, the usbc to usb adapter is extremely durable and sturdy. Rigorously tested to withstand more than 10,000 times of plugging and unplugging, ensuring long-lasting performance
- Broad Compatible: The usb c to usb adapter widely supports all USB C/ USB A devices like laptops, tablets, cellphones, car chargers, and phone chargers. Such as compatible with MacBook Pro/Air 2023/2022, Thunderbolt 4/3 Devices,Apple MagSafe Watch 9/8/7/SE/Ultra, iPad Pro 2022/2021, Samsung Galaxy S23/S20/S10, and iPhone 17/16/15 Pro. Plug and play
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
- Capped or tiered fees: A cap changes the calculation once the fee reaches its limit. For example, PayPal’s US fee schedule lists an ACH Services charge of 0.80%, capped at $5 per transaction. That fee cannot be modeled with the unmodified percentage-plus-fixed formula; calculate against the actual cap rule.
- Other charges: Taxes, discounts, currency conversion, or additional processor fees are not included unless you explicitly model them. If a percentage surcharge applies to the gross, include it in the percentage rate only if its terms use that same base.
- Refunds: A gross-up does not make a later refund cost-neutral. Stripe states that original payment-processing, Connect, and currency-conversion fees are not returned on refunds.
- Rounding: Round the calculated gross to the smallest invoiceable unit, then recalculate the estimated fee and net. Rounding down can leave you short. The cited pricing pages do not establish a universal fee-rounding rule across every method and currency, so check the rules that apply to the transaction.
Compare fees using your actual transaction mix
To compare Stripe and PayPal for your business, use the matching fee terms rather than a single headline rate. Compare the applicable percentage, fixed fee and currency, payment method, domestic or international status, and any conversion or other additional fees. Then calculate using your real transaction amounts and expected mix: a fixed fee has a greater effect on smaller charges. The available pricing schedules do not establish that either processor is cheaper for every seller.
Do these 3 things before closing this tab:
1Fix the driver behind crashes, sound loss and screen glitches2Clear out junk files and repair common Windows errors3Scan for outdated or missing drivers - takes under a minuteQuick Recap
Best Value
- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
