Start with the import requirements
Check the allowed characters, total length, file format, and heading with your vendor before making the list. Use a campaign prefix such as FALL_ to distinguish one campaign from another.
Sequential numbers work when you want a traceable list. A prefix of COUPON_, six digits, and a start of 1 produces COUPON_000001. The zeros fill the six-digit number; the complete code has 13 characters.
Random codes suit lists that should not simply count upward. The default character set leaves out I, O, 0, and 1 to reduce confusion when someone reads or types a code. You can also choose letters only or digits only.
Review, export, and import
Generate up to 50,000 codes. The preview shows the first 100; copying or downloading includes the full batch. The Excel file contains one text column, so 000123 stays 000123. Choose CSV when your vendor requires it, and check whether they want the Code heading.
Try a small import before sending the full list. This tool creates codes locally in your browser and does not send them to your vendor or save a campaign history. Editing the format clears the previous result so you cannot accidentally download a list made with older settings.
How uniqueness works
Random codes use the browser’s cryptographic random-number API. Repeated candidates are discarded within the current batch. Requests larger than the available combinations are rejected; for example, two digits allow only 100 distinct codes.
Sequential codes advance by one and are padded to your chosen length. The tool rejects a batch that would overflow that length. Use Next batch to continue after the last generated number. For standard technical identifiers with a fixed format, use the UUID generator.