Free tool / no upload

UID CSV validator for card personalization files

Paste or drop the identifier file for a card order and audit it before anyone imports it: malformed values, duplicates and mixed byte lengths are flagged, and a normalized working file is one click away.

Identifier CSV validator
All calculations run in this browser. Inputs are not uploaded or stored by ChargeRFID.

CSV / BATCH QA

Identifier CSV validator

Audit the identifier column for malformed values, duplicates and mixed byte lengths, then download a normalized working file.

CSV / TXT
All calculations run in this browser. Inputs are not uploaded or stored by ChargeRFID.
Paste at least one identifier row to begin.
CSV

Paste at least one identifier row to begin.

What breaks identifier imports

Most failed backend imports trace back to the file, not the cards. Spreadsheets silently convert long decimal identifiers to scientific notation, strip leading zeros and reformat columns. Exports from different systems mix 4-byte and 7-byte values in one list, and copy-paste editing introduces duplicates.

Each of these problems is invisible when you scroll through the file and obvious once every row is parsed. Validating before import is minutes; discovering the problem after 5,000 cards are personalized is a reorder.

What the validator checks

The tool auto-detects the delimiter and the identifier column, then parses every row. It counts valid identifiers, flags values that are not clean hexadecimal at a supported length, lists duplicates with their row numbers, and reports every byte length found in the file.

A consistent file shows one byte length, zero invalid rows and zero duplicates. Anything else is listed in the issue log with the exact row, so the person who owns the file can correct it at the source.

The normalized output file

After analysis you can download a normalized CSV: identifiers uppercased, separators removed, columns preserved. Using the normalized file on both sides of a handover removes the formatting drift that causes most reconciliation exceptions later.

Like every tool on this site, parsing runs entirely in your browser. The file never leaves your device, which makes the validator safe for production personalization data.

CSV validation questions

CSV validation questions

Spreadsheets treat long digit strings as numbers: they drop leading zeros, round values above 15 digits and display scientific notation. Keep identifier columns formatted as text, or exchange identifier files as plain CSV edited in a text editor.

Paste the file into the validator: duplicates are counted and listed with their row numbers after normalization, so 04A1B2C3 and 04:a1:b2:c3 are recognized as the same identifier. Duplicates in a personalization file usually mean a copy-paste or export error.

Mixed 4-byte and 7-byte values usually mean the list was merged from two sources, or one source truncated identifiers. A backend expecting one fixed length will reject or mis-match the rest, so resolve the length question before import.

No. The file is read and parsed locally in your browser and is not transmitted to or stored by ChargeRFID. You can disconnect from the network after loading the page and the validator still works.

Engineer review

Want a second pair of eyes on this result?

Leave a work email and a ChargeRFID credential engineer replies with a short assessment of your format situation, usually within one business day. Only your email and your note are sent; your identifier data never leaves this browser.

No newsletter, no list. One reply from one engineer.

Clean file, clean import, clean delivery.

ChargeRFID delivers personalization data in the exact format your backend expects, with a data contract and acceptance vectors included with every order.