All tools · page 232
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Formats DTSTART;VALUE=DATE date-only lines for all-day calendar QR codes.
Composes RRULE repeat rules for weekly, monthly, and custom recurrence in event codes.
Adds TZID parameters and UTC offsets so event codes fire at the correct local time abroad.
Builds BEGIN:VCARD 3.0 strings with name, phones, email, org, and URL fields.
Creates 4.0 contact strings with TZ, social URLs, and correct TYPE parameters.
Builds compact MECARD strings that many scanners parse fastest for contact sharing.
Maps cell, work, home, fax, and pager TYPE parameters into correct vCard TEL lines.
Escapes commas, semicolons, and backslashes in structured names and addresses.
Rewrites MECARD strings as full vCards for migrating legacy contact codes.
Estimates Base64 photo growth against QR version capacity before encoding contact photos.
Merges several contacts into one vCard payload and warns when it outgrows QR version 40.
Compares how iOS, Android, and Outlook ingest vCard versus MECARD contact codes.
Builds otpauth://totp URIs with issuer, account, secret, digits, and period for 2FA enrollment codes.
Creates otpauth://hotp strings with initial counter values for event-based tokens.
Converts hex or ASCII shared secrets into RFC 4648 Base32 for authenticator apps.
Encodes one or more TOTP secrets into otpauth-migration:// batch QR strings for app transfer.
Percent-encodes issuer and account labels including the issuer:account colon separator.
Shows the 45-character alphanumeric mode alphabet and when lowercase forces byte mode.
Computes the XOR parity byte and sequence headers for splitting payloads across multiple QR symbols.
Generates apple-itunes-app meta tags and Android intent blocks that pair with printed codes.
Composes custom scheme:// URIs with path and query parameters for installed-app routing.
Plans app-scheme and web fallback chains so one code works on iOS, Android, and desktop.
Compares 1D barcodes against 2D codes on data capacity, scanner needs, and cost.
Checks VPA handle structure and bank suffixes before embedding in payment codes.