Free HOTP QR Code Generator
Build standard otpauth://hotp/ QR codes for counter-based authenticator apps and hardware tokens. Pure RFC 4226, no server, no signup.
- Gerador de QR Code
- Criador de Cartões de Visita Grátis
- Cartões WiFi Imprimíveis
- CSV em Lote (500 códigos)
- 40 Modelos
- 20 Idiomas
Este formato de código de barras é renderizado em monocromático apenas com cores de primeiro plano e de fundo. Modelos, formas de pontos/olhos, gradientes, molduras e logos centrais aplicam-se apenas a códigos QR e estão ocultos aqui.
Mostrar mais 30 modelos
Salve um estilo com o botão acima para manter seus favoritos aqui.
Ou escolha um ícone integrado:
Mostrar mais 108 ícones
Renderizado atrás do QR com opacidade reduzida. Força automaticamente EC=H para que o QR continue legível através da foto.
Geração em Lote
Envie um CSV para gerar até 500 QR Codes em um único lote. Cada linha se torna seu próprio QR — escolha um modelo ou personalize 21 propriedades por linha: cores, molduras, estilos de pontos/olhos/pupilas, gradientes, transparência, tamanho, correção de erros, formato, logo integrado e muito mais.
21 colunas: type, data, filename, frametext, frame, template, fgcolor, bgcolor, size, ec, dotstyle, eyestyle, format, logo, gradient, g2, gtype, gangle, transparent, eyeball, eyecolor. Apenas type e data são obrigatórios. Use | para separar campos dentro de data (ex.: ssid|password|WPA).
Todos os 20 tipos de QR são suportados, incluindo URL, WiFi, vCard, MeCard, Email, SMS, Event, Location, UPI, SEPA, PayPal, Crypto, Micro QR e rMQR. Baixe o CSV de exemplo para ver todas as colunas, os 40 modelos, os 11 estilos de moldura e os 12 logos integrados em ação.
1. Baixe o CSV de amostra · 2. Edite no Google Sheets, Excel, Numbers ou em qualquer editor de texto · 3. Faça upload aqui
Salve todo o QR Code – tipo, todos os valores dos campos, estilo, estrutura, logotipo, design do cartão de visita – como um único arquivo .qr.json. Carregue-o mais tarde para recriar tudo em um clique.
Digite o conteúdo para gerar seu QR code
Assinaturas eletrônicas com validade jurídica
O Abundera Sign vai além das assinaturas eletrônicas básicas. Cada documento recebe prova criptográfica, verificação independente e um pacote de evidências à prova de adulteração.
- Pacotes de evidências prontos para tribunal, gerados automaticamente
- Selo Pessoal de Documento — detecta adulterações instantaneamente
- Ancorado em 5 sistemas independentes — sem ponto único de falha
How HOTP Differs from TOTP
HOTP and TOTP both produce 6- to 8-digit one-time codes from a shared Base32 secret, and both use the same otpauth:// URI scheme. The single difference: TOTP advances the code on time (typically every 30 seconds), while HOTP advances on a counter that the client increments each time it generates a code. The server tracks the same counter and accepts codes within a small look-ahead window.
HOTP is the right choice when you can't trust the device clock, when the device has no clock (hardware tokens), or when codes need to remain valid until they are used (login flows where typing time matters). The trade-off is that the counter can drift if the user generates codes without submitting them — most servers handle this with a re-sync window of 10 to 50 codes.
Where HOTP shines
- YubiKey OTP slot — the original use case. Press the button, the YubiKey emits the next HOTP code as keystrokes.
- Hardware tokens — Feitian c100, RSA SecurID 700-series, programmable tokens from Token2 and Protectimus. All ship with HOTP firmware.
- Air-gapped systems — submarines, remote sensors, factory-floor terminals where time sync is unreliable but a counter is durable.
- Server-side OTP backup — single-use recovery codes are HOTP under the hood, with the counter incremented per use.
Fields explained
- Issuer — service name (e.g. GitHub). Shown as the heading in the authenticator app.
- Account — usually your username or email. Shown as the subheading.
- Secret — Base32-encoded shared secret. 16, 26, or 32 characters typically.
- Algorithm — SHA1 (default), SHA256, or SHA512.
- Digits — 6 (default) or 8.
- Initial counter — usually 0. Set to a higher value if re-provisioning a token that has already been used.
Privacy
The shared secret is sensitive. Abundera QR runs entirely in your browser — the secret never touches a server, never gets logged, never leaves your device. Generate on an offline laptop for maximum paranoia.
Disponível em 26 idiomas
Interface totalmente traduzida, renderização nativa de escrita e suporte da direita para a esquerda para árabe e urdu.
Frequently Asked Questions
Which apps and tokens can read these HOTP QR codes?
Any standards-compliant HOTP implementation: Aegis, Raivo, FreeOTP, FreeOTP+, KeePassXC, Yubico Authenticator, Token2 personalization tools, Protectimus desktop tools, and most modern enterprise IAM platforms (Okta, Auth0, Keycloak). Note: Google Authenticator quietly ignores the counter parameter and treats everything as TOTP — pick a different app for HOTP setups.
How is HOTP different from a YubiKey FIDO2 / WebAuthn key?
Different protocol entirely. HOTP is a shared-secret one-time-code scheme (RFC 4226). FIDO2/WebAuthn is asymmetric public-key authentication. Both are 'second factors' but FIDO2 is phishing-resistant where HOTP is not. HOTP is a fit when the relying party only supports OTP, or when you specifically need a code that can be typed.
What happens if the counter drifts out of sync?
Most servers accept codes within a look-ahead window (typically 10 codes) and resync the counter when a valid forward code arrives. If drift exceeds the window the user has to re-enroll. Some IAM platforms expose a 'resync' admin action that takes two consecutive codes to recompute the offset.
Why does Google Authenticator give wrong codes for HOTP QRs?
Google Authenticator treats every otpauth:// QR as TOTP regardless of the path. The codes it produces are valid TOTP codes against your secret — not HOTP codes — so the server rejects them. Use Aegis, Raivo, Yubico Authenticator, or a hardware token instead.
Can I program a YubiKey OTP slot from this QR?
Not directly. YubiKey OTP slots are programmed with the YubiKey Manager (GUI) or ykman (CLI). You can copy the Base32 secret from the form into ykman: ykman oath accounts add --type HOTP --algorithm SHA1 --digits 6 ISSUER:ACCOUNT <secret>.
What's the maximum counter value?
RFC 4226 allows counters up to 2^63 - 1. Practically, most implementations cap it lower (32-bit on legacy hardware). Hundreds of thousands of presses is fine on any modern token.
Should I use HOTP or TOTP for new deployments?
TOTP for almost everything. HOTP is the right pick only for: hardware tokens that lack a clock, deeply air-gapped environments, or single-use recovery codes. For phone-based 2FA, time-based codes are the standard and the user experience is significantly better.