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Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Clear out junk files and repair common Windows errorsFree Scan →To automatically generate a shipping label image, create a shipment through a carrier or shipping-platform API, request a supported output format such as PNG, and save or download the returned file. The right endpoint depends on where you ship: DHL eCommerce creates one label per request and returns PNG or PDF data as Base64; Walmart’s label endpoint selects PNG or PDF through the request’s Accept header; ShipStation supports PNG, PDF, or ZPL, with 4×6 and letter layouts. If you need an image for an application, request PNG where available. For broad carrier compatibility or printing, PDF is often the safer choice.
Choose the API and format for your shipping workflow
A label API does more than draw a graphic: it creates a shipment, assigns carrier and tracking information, and returns a carrier-usable label. You generally cannot make a valid shipping label from an address alone. You need shipment details and access to a carrier or shipping platform that can book or create the shipment.
| Option | Useful for | Documented label output | Important constraint |
|---|---|---|---|
| DHL eCommerce Americas Label API v4.0.0 | Shipments using DHL eCommerce | PNG, PDF, or ZPL; PNG and PDF are Base64-encoded, while ZPL is plain text | POST /shipping/v4/label creates one label per request and requires a unique packageId. |
| ShipStation Labels API | Multi-carrier label workflows managed through ShipStation | PDF, PNG, or ZPL; download by URL or inline data | Documented layouts are 4x6 and letter. ShipStation recommends PDF because it is supported by all carriers, while PNG and ZPL support varies. |
| Walmart Marketplace Create label API | Eligible Walmart Marketplace shipping workflows | PDF or PNG, selected with the HTTP Accept header |
The documentation lists FedEx and USPS as currently supported carriers. |
DHL Freight has a separate Print API for PDF and ZPL output. Its documentation includes ZPL for 203, 300, and 600 DPI label printers; do not assume that this is the same API or coverage as DHL eCommerce. See the DHL Freight Print API documentation.
Pick output for its destination
- PNG: Choose it when your application needs a raster image to display, attach, or pass to another image-processing step. PNG availability and support depend on the selected API and carrier.
- PDF: Prefer it when you need a printable document or wider carrier compatibility. ShipStation explicitly recommends PDF because all carriers support it, whereas PNG and ZPL support can vary.
- ZPL: Use it when your label printer accepts ZPL and the carrier/API supports that format. It is printer-language text, not a PNG image; confirm printer language and DPI before sending it to the device.
Choose the layout and delivery method
A 4×6 layout is commonly used with thermal label printers; letter layout is appropriate when you need a standard paper sheet. ShipStation documents both 4x6 and letter. Confirm the exact layout options supported by the endpoint you select. Also check whether the API returns file content inline or a URL that your service must fetch. A URL may have a limited lifetime; the provider’s documentation should determine how long it remains usable.
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- Bluetooth Wireless Connection: KNAON Bluetooth shipping label printer enables wireless printing. For Mobile users, download the 'FlashLabel Pro' app from APP Store or Google Play for printing. Also, supports Windows and macOS, and can directly connect to the printer by downloading the 'FlashLabel Pro' App. Windows 7 or later computers can also print via Bluetooth by installing the latest advanced driver. Note: All devices CANNOT be connected directly to Bluetooth, and must be used through the 'FlashLabel Pro' app.
- USB Cable Connectivity: This printer ensures seamless USB connectivity with macOS, Windows (7 and above), ChromeOS, and Linux. KNAON printer features a built-in USB drive preloaded with drivers and tutorial videos for a fast and hassle-free setup. For ChromeOS, need to install 'FlashLabel' extension to your Google Chrome.
- Versatile DIY Labeling Options: KNAON Thermal Shipping Label Printer offers a vast selection of pre-designed templates, including 3,000+ templates, 5,000+ icons, and 100+ fonts available in the app. Designed for both professional and personal use, it supports various thermal paper sizes, ensuring effortless customization for all your labeling needs. Ideal for printing DIY shipping labels, barcode labels, thank-you labels, mailing labels, name tags, price tags, and various small thermal labels.
- Seamless Multi-Platform Compatibility: This Bluetooth shipping label printer works effortlessly with all major platforms, including Amazon, eBay, Shopify, USPS, UPS, Etsy, PayPal, Poshmark, DHL, and more, ensuring smooth and efficient label printing. (Note: Save the logistics label as a PDF file on the shipping platforms, then import it into the 'FlashLabel Pro' app for printing).
- Portable & Stylish Design: KNAON multi-function thermal label printer offers user-friendly operation in a compact design. Its perfect size (7.17 x 3.9 x 3.43 inches) makes it simple to store anywhere. With a fast printing speed of up to 180 mm/s and support for paper widths from 1.5 to 4.2 inches. The package also includes 10 test printing papers to get you started right away.
Build the label-generation workflow
- Collect shipment data. Gather ship-from and ship-to addresses, package weight and dimensions, selected service, and a unique order or package identifier. Required fields vary by provider and shipping service.
- Validate and authenticate. Check required fields and address formatting before calling the API, then authenticate using that provider’s current instructions. Store credentials securely rather than embedding them in a client-side app.
- Create the shipment and request the output. Choose a supported format and layout. For a raster workflow, request PNG; for a portable print document, request PDF. Some APIs use a request field, while Walmart’s endpoint uses the
Acceptheader. - Interpret the response correctly. Determine whether the payload is Base64, raw bytes, text such as ZPL, or a download URL. Decode or fetch it as specified by the API. Do not save Base64 characters as if they were the PNG file.
- Persist and associate the result. Store the file or a controlled reference to it with the order/package identifier and the returned tracking identifier. Provide an authorized reprint path and define retention and access rules for label files.
- Verify before production. Print sample labels at the intended physical size and printer resolution. Test scanner readability and confirm that the carrier accepts the label in the geography and service you use.
Request PNG from Walmart’s label endpoint
Walmart documents PNG selection through the Accept header. The header value is application/json,image/png; PDF can be requested with application/json,application/pdf. The endpoint accepts shipment information and returns a tracking number plus label output. The documented carrier options are FedEx and USPS. The example below shows the format-selection pattern, not a complete shipment request: add the endpoint’s required shipment body and the authentication required by your Walmart Marketplace account before using it.
curl -X POST "https://marketplace.walmartapis.com/v3/shipping/labels"
-H "Accept: application/json,image/png"
-H "Content-Type: application/json"
-H "WM_SEC.ACCESS_TOKEN: $WALMART_ACCESS_TOKEN"
-d '{
"shipment": {
"carrier": "FEDEX"
}
}'
-o label.pngThe sample URL and body illustrate the endpoint and format choice; use the current Walmart documentation for the exact request schema, required headers, and account authorization. A response may include structured data as well as label content, so inspect the actual response before treating the entire response body as a PNG file. If the endpoint returns an image payload directly, save its bytes; if it returns an encoded field or a URL, decode or fetch that value instead.
For a PDF response, change the requested media type and use an appropriate file extension, for example Accept: application/json,application/pdf and -o label.pdf. A file extension does not convert the content: it must match the actual response format.
Handle Base64 label data from DHL eCommerce
DHL eCommerce Americas Label API v4.0.0 uses POST /shipping/v4/label. Each request creates one label, so generate a distinct request with a unique packageId for every package. The response includes DHL and tracking identifiers. PNG and PDF label contents are Base64-encoded, while ZPL is returned as plain text. The exact authentication headers, request schema, and response field names should be taken from the DHL eCommerce API reference.
When the response contains Base64 PNG content, decode that field into bytes before writing the file. For example, after parsing a JSON response into data and identifying the documented field that contains the Base64 label, Python can save it like this:
Rank #2
- Bluetooth Wireless Connection: KNAON Y41BT Bluetooth shipping label printer enables wireless printing. For iOS and Android users, need to download the 'FlashLabel Pro' App from Apple Store or Google Play. Windows 7 or later computers can also print via Bluetooth by installing the latest advanced driver. Mac users with M1/M2/M3/M4 processors can connect to the printer by downloading the 'FlashLabel Pro' App from Apple Store. Note: All devices CANNOT be connected directly to Bluetooth, and must be used through the 'FlashLabel Pro' app.
- USB Cable Connectivity: This printer ensures seamless USB connectivity with macOS, Windows (7 and above), ChromeOS, and Linux. KNAON printer features a built-in USB drive preloaded with drivers and tutorial videos for a fast and hassle-free setup. For ChromeOS, need to install 'FlashLabel' extension to your Google Chrome.
- Versatile DIY Labeling Options: KNAON Thermal Shipping Label Printer offers a vast selection of pre-designed templates, including 3,000+ templates, 5,000+ icons, and 100+ fonts available in the app. Designed for both professional and personal use, it supports various thermal paper sizes, ensuring effortless customization for all your labeling needs. Ideal for printing DIY shipping labels, barcode labels, thank-you labels, mailing labels, name tags, price tags, and various small thermal labels.
- Seamless Multi-Platform Compatibility: This Bluetooth shipping label printer works effortlessly with all major platforms, including Amazon, eBay, Shopify, USPS, UPS, Etsy, PayPal, Poshmark, DHL, and more, ensuring smooth and efficient label printing. (Note: Save the logistics label as a PDF file on the shipping platforms, then import it into the 'FlashLabel Pro' app for printing).
- Portable & Stylish Design: KNAON multi-function thermal label printer offers user-friendly operation in a compact design. Its perfect size (7.2 x 3.15 x 2.65 inches) makes it simple to store anywhere. With a fast printing speed of up to 180 mm/s and supports paper widths from 1.38 to 4.41 inches. The package also includes 20 test printing papers to get you started right away.
import base64
from pathlib import Path
# data is the parsed JSON response. Replace "label" with the
# Base64 field name documented for the response you receive.
encoded_label = data["label"]
Path("label.png").write_bytes(base64.b64decode(encoded_label))Do not assume that the response field is named label; use the actual field name specified by the API response schema. For PDF, use a .pdf filename. For ZPL, preserve the text exactly and send it only to a compatible printer or print workflow.
Generate and print a correct 4×6 label
Requesting a 4×6 layout is only one part of producing a usable label. The API must support that layout, the file must be printed at its intended physical size, and the printer must support the chosen format. ShipStation documents 4x6 and letter layouts; check the selected carrier and service’s requirements as well.
- Set the layout explicitly where the API exposes a layout option; do not rely on a viewer’s default scaling.
- In the print dialog, use actual size or the equivalent setting rather than “fit to page” if that would change label dimensions.
- For ZPL, match the printer language and supported DPI. DHL Freight documents ZPL options at 203, 300, and 600 DPI.
- Scan a printed test label and verify that barcodes remain legible at the actual printer speed and media setting.
- Test the file and printer combination for the carrier, service, and destination market before automating a high-volume workflow.
Keep label storage and reprints reliable
Make label generation part of an order’s lifecycle rather than a one-off file download. Save enough metadata to connect the label to its shipment, but do not treat a local filename as the only record of which package it belongs to.
- Use the carrier/platform tracking identifier and your own unique order or package ID to associate the result.
- Persist inline file bytes when you need dependable reprints. If the API gives a temporary URL, fetch and store the file promptly unless the provider documents longer availability.
- Define how duplicate requests are handled. DHL eCommerce requires a unique
packageIdfor each created label; consult the provider’s rules for correcting, voiding, or reprinting a shipment. - Restrict access to label files and set a retention policy suitable for your shipping operations.
- Record the response status and provider identifiers so failed generation can be retried or investigated without accidentally associating a label with the wrong parcel.
Common problems and fixes
The saved PNG will not open
The response may be JSON containing Base64 rather than raw image bytes, or it may contain a URL. Inspect the response content type and schema, then decode the documented Base64 field or fetch the URL. Renaming JSON or Base64 text to .png does not create an image.
The Walmart response is not an image
Check that the request uses the documented Accept: application/json,image/png value and that the response actually contains image bytes. The API also returns tracking information, so the body may not be a standalone PNG in every response shape. Follow the endpoint’s current response schema instead of blindly saving the entire response.
Rank #3
- Go Wireless by Bluetooth: Download the "NELKO"app to print via Bluetooth on your Nelko Bluetooth thermal label printer for iOS and Android. Printing shipping labels has never been easier. Windows 7 or later computers can also print via Bluetooth. For Mac users with M1 or M2 CPUs, install the app and connect to the printer via Bluetooth. Note: All devices cannot be directly connected to Bluetooth and need to be used through the app
- Print via USB: For Windows (7 and later), Mac OS,Chrome OS, you can connect the desktop label printer via USB cable. Note that Mac OS only works with USB connection, you can not print via Bluetooth
- Good Helper for Cost Saving: Advanced thermal direct technology is adopted to achieve the printing speed of 150 mm/s, up to 72 sheets 4x6 labels/min. High speed brings high efficiency and helps your business grow faster! 203 DPI makes printing clearer. No ink, no toner, only thermal labels needed. Both fanfold labels and roll labels could be used. Label size: labels width ranges from 1.54" to 4.1"(40-104 mm), such as 4x6, 3x2, 3x1, 2x1 thermal labels and so on
- Strong Platform Compatibility: This bluetooth shipping label printer can work with virtually all platforms, including Amazon, Ebay, Shopify, USPS, UPS, Esty, PayPal, Poshmark,etc.(Note: Please remember to save the logistics label as a PDF on the logistics platform, then upload it to the editor APP "NELKO" for printing
- Suitable for Commercial and Home Use: Printer driver, instruction videos and problem shooting videos are provided in U-Disk for better setting. Nelko PL70E label printer is much smaller than traditional printers and only requires a small piece of space to achieve printing. Very suitable for printing shipping labels, mailing labels, price labels, barcode labels, name tags and all kinds of small category labels
The API rejects a DHL label request
Check required shipment fields, credentials, and the request schema for DHL eCommerce API v4.0.0. Ensure each label-creation request uses its own unique packageId; the operation creates one label per request.
The label prints at the wrong size
Confirm that the requested layout is supported, the print dialog is not scaling the page, and the printer media matches the intended label. For a thermal workflow, validate the physical 4×6 dimensions and barcode scan before deploying.
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The printer produces blank output or unreadable characters
Check the file format. PNG and PDF are not interchangeable with ZPL. Send ZPL only to a compatible label printer, and ensure its DPI setting matches the output option supported by the relevant API.
A reprint link no longer works
The provider may return a temporary URL. Fetch and persist the file when it is created, or confirm the provider’s URL lifetime and request a fresh label through its documented shipment workflow. Follow the provider’s rules before creating a replacement label, since duplicate labels can complicate fulfillment.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Costs, latency, and production considerations
These API references establish formats and workflows, not a universal per-label price, response-time guarantee, or uptime figure. Confirm the selected carrier or platform’s account eligibility, shipping charges, API limits, and current commercial terms directly with that provider. Add bounded retries for transient network errors, but do not blindly repeat a shipment-creation request: first determine whether the original request succeeded and whether it created a shipment or label.
Rank #4
- [HIGH TECH LABEL PRINTER] Equipped with a Japanese high tech thermal print head, 203 DPI high printing quality. No ink, No toner, Clean with no mess, economical. Works with both fanfold labels and roll labels. Label size: labels width ranges from 1.57" to 4.1"
- [PRINT WIRELESSLY]The label printer support printing wirelessly. For windows 8 or later and Mac, you can print via Bluetooth. For Android& iOS, you can’t print via Bluetooth on phone, need to download the App "Jadens printer" and print on it.
- [PRINT VIA USB] USB connection works with both Windows (7 and newer) and Mac OS (10.9 and newer) devices. Please long and press the feed button to identify and calibrate label size each time you change labels.
- [WIDE USAGE] JADENS thermal label printer is widely used to print labels from various marketplaces and shipping platforms, such as Endicia, Dazzle, ShipStation, Shipping Easy, Shippo, ShipWorks, Ordoro, eBay, Amazon, Easy, and Shopify. Use JADENS thermal label maker machine to print shipping labels, warehouse labels, market labels, helping increase your productivity. Ideal for your online small business for shipping packages.
- [EASY TO SET UP & RELIABLE AFTER-SALE SERVICE] Set up in one minute. Printer driver, instruction videos and problem shooting videos are provided in U-Disk for better understanding. Offer one year warranty; customer support can be reached out to email, phone, remote control.
For throughput, DHL eCommerce’s documented operation creates one label per request, so a multi-package order requires handling each package as a separate label creation with unique identifiers. Persist successful results as they arrive and track failures per package rather than treating the whole order as one indivisible request. For any provider, test how authentication expiry, carrier outages, malformed addresses, and partial shipment completion should be represented in your own application.
Or skip the browser setup
ScreenshotNeo is a website screenshot API and MCP server, not a shipping carrier or label-creation API. If your workflow already produces a label page or preview in a browser and you need a clean screenshot of that page, one GET request can capture it. It does not replace the carrier step that creates a valid, trackable shipping label. See the ScreenshotNeo service and its API documentation.
curl -G "https://api.screenshotneo.com/v1/shot" -d access_key=YOUR_API_KEY --data-urlencode url=https://stripe.com -o shot.webpFor a label-page capture, replace the example URL with the URL of a page you are authorized to access. ScreenshotNeo can remove cookie banners, newsletter popups, and chat widgets before capture; bot checks, blank pages, and failed loads are not billed. Its MCP server lets AI agents take screenshots. The free plan includes 1,000 screenshots a month with no card, and paid plans start at $5 for 3,000. Sign up for the free plan.
Frequently asked questions
Can I generate a shipping label PNG from an API?
Yes, if the carrier or shipping platform supports PNG for the shipment. DHL eCommerce and Walmart document PNG output, and ShipStation lists PNG as a label format. Check the selected service’s support before relying on it in production.
Can I make a valid label from only an address?
Not through the documented workflows here. Label creation requires shipment information and a carrier or platform operation; collect the package and service details that the chosen API requires.
Should I use an image screenshot as my shipping label?
No. A screenshot can document or display a label page, but it does not create the shipment or guarantee a carrier-accepted label. Use the carrier or platform’s label output for fulfillment.
Quick Recap
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.
