Mask API
Mask a value for safe display. The mask endpoint keeps the first and/or last few characters visible and replaces the rest with a mask character — so a card becomes ••••••••••••1111 and an API token becomes sk**********3456 — and can keep separators (spaces and dashes) intact so the value keeps its shape. A dedicated email masker hides the local part (and optionally the domain) while keeping the address recognisable, e.g. j•••••••@example.com. Choose how many characters to reveal and which mask character to use. Perfect for showing the last four digits of a card, partially hiding emails and phone numbers, and masking tokens and account numbers in UIs, receipts and logs. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This masks a known value for display; to find and redact PII inside free text, use a redaction API.
api.oanor.com/mask-api