--- title: "Attest vs ZapSign and D4Sign · Attest" description: "Attest vs ZapSign and D4Sign (Brazil) on encryption, ICP-Brasil certificates, checking a document later and price in reais, as published on October 12, 2026." url: https://attest.datahubz.com/compare/attest-vs-zapsign-and-d4sign updated: 2026-10-12 --- [Attest](https://attest.datahubz.com/)/[Compare](https://attest.datahubz.com/compare) # Attest vs ZapSign and D4Sign Attest is the better choice when a contract's content must stay private and provable: it end-to-end encrypts every document in your browser so Attest can't read it, each signer signs with a passkey only they control, and the signed copy verifies on its own, for $5 a month (about R$25 at the PTAX rate of October 9, 2026) for 20 documents. ZapSign and D4Sign are stronger for ICP-Brasil certificate signatures and identity checks against Brazilian databases, with 20-document plans from R$29.90 a month at ZapSign (paid yearly) and R$35.91 at D4Sign (billed annually), as published on October 12, 2026. By DataHubz · Updated October 12, 2026 · 8 min read ## ZapSign, D4Sign and Attest at a glance **ZapSign**, based in São Paulo and Belo Horizonte, was founded in 2020 and has been part of Truora, a Latin American digital identity company, since May 2022; it states "+8 milhões de usuários". It is also an ICP-Brasil certification authority accredited by ITI. **D4Sign**, based in São Paulo, is "Uma empresa do Grupo Zucchetti" (a Zucchetti Group company) and holds ISO 27001. Attest is built around a different promise: proof anyone can check, on documents only the parties can read. Prices are as published on October 12, 2026; other details as published on each vendor's pages on October 11, 2026. | | Attest | ZapSign | D4Sign | | ----------------------------- | -------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------- | | What it says about encryption | Every document end-to-end encrypted in your browser; Attest can't read it | "não temos acesso ao conteúdo dos seus documentos" (we do not have access to the content of your documents); no mechanism described | "Todos os dados são criptografados de ponta a ponta" (all data is encrypted end to end); no mechanism described | | How a signer signs | A passkey only they control (Face ID, Touch ID, Windows Hello or the device PIN) | A link, with email code included; WhatsApp, SMS, selfie, CPF and facial checks, some paid per use | A link plus name, CPF and date of birth; 15 or more checks, from Pix to selfie and video | | What seals the signed PDF | Each signer's own signature, plus a public blockchain anchor | ZapSign's own A1 ICP-Brasil certificate | D4Sign's own certificate; signers' ICP-Brasil certificates at no extra cost | | Checking it later | Anyone, free: the open-source verifier inside the signed copy | ITI's validator, Adobe Reader or ZapSign's checker | D4Sign's verifier; ITI only for certificate signatures | | Free | 2 documents, in total | 3 documents a month, free forever | 30-day trial, no card | | 20 documents a month | $5 a month (about R$24.95 at the PTAX rate of October 9, 2026) | R$39.90 a month, or R$358.80 a year paid upfront (R$29.90 a month) | R$39.90 a month, or R$430.92 a year (R$35.91 a month) | ## "No access" and "end to end": who holds the key? ZapSign says: "Nossos servidores estão hospedados na Amazon Web Services e não temos acesso ao conteúdo dos seus documentos" (our servers are hosted on Amazon Web Services and we do not have access to the content of your documents), and that data travels over HTTPS/TLS and is stored on "servidores seguros" (secure servers). D4Sign's help center says "Todos os dados são criptografados de ponta a ponta, garantindo que as informações só possam ser acessadas por pessoas autorizadas" (all data is encrypted end to end, so that only authorized people can access it), and that documents are stored on Amazon Web Services "com criptografia". Neither page describes the mechanism: where a document is encrypted, and who holds the key that opens it, the two answers that decide whether a service can read your contracts. D4Sign's Profissional plan also includes D4Sign.AI, with summaries of and chat about your documents, features that work on a document's contents. Attest answers both questions in its design. Each document is encrypted in the sender's browser with AES-256-GCM, its key is locked separately to each party's own key, and it is decrypted only in the parties' browsers. Attest stores your document only as ciphertext it can't read, and it has no AI features that process documents. We compared 21 e-signature services in October 2026, Attest and 20 others, and [Attest was the only one](https://attest.datahubz.com/compare/which-e-signature-services-can-read-your-documents) that end-to-end encrypts every document, for every signer, by default. ## ICP-Brasil, and what Brazilian law asks This is general information, not legal advice. Under [MP 2.200-2/2001](https://www.planalto.gov.br/ccivil%5F03/mpv/antigas%5F2001/2200-2.htm), art. 10, a document signed with an ICP-Brasil certificate is presumed true in relation to its signers, and other methods of proving authorship and integrity are valid when the parties admit them or the person the document is used against accepts them. Most contracts between private parties can use either; some acts can't use a simple signature, such as real estate deeds above the legal threshold (a public deed, [Código Civil](https://www.planalto.gov.br/ccivil%5F03/leis/2002/l10406compilada.htm) art. 108), electronic or remote notarial acts (only through e-Notariado) and the cases where [Lei 14.063/2020](https://www.planalto.gov.br/ccivil%5F03/%5Fato2019-2022/2020/lei/l14063.htm) requires a qualified signature. Both vendors serve the ICP-Brasil route well. As published on October 12, 2026, ZapSign charges R$0.50 per certificate signature on Profissional and Equipe, and its Equipe plan includes one ICP-Brasil certificate for new subscribers, as a limited-time offer (e-CPF or e-CNPJ, A1, or A3 in the cloud, valid one year; list price R$160 to R$260). ZapSign also notes that being a certification authority "não torna toda assinatura eletrônica uma assinatura qualificada" (doesn't make every electronic signature a qualified one). D4Sign accepts signers' own ICP-Brasil certificates, including cloud certificates, on every plan at no extra cost. An Attest signature is an electronic signature outside ICP-Brasil, signed with the signer's own passkey. For an ordinary contract, add a clause in which the parties accept the signing method. ## Checking a signed document later **ZapSign** certifies each signed PDF with its own A1 ICP-Brasil certificate, so the file can be checked on ITI's validator (validar.iti.gov.br) or in Adobe Reader, which needs the certificate chain imported for documents signed before July 20, 2023; ZapSign also runs its own authenticity checker. Its help pages disagree on long-term validation: one says "Ainda não oferecemos PAdES-B-LT ou LTA" (we don't yet offer PAdES-B-LT or LTA), another that long-term validation data is now embedded in ICP-Brasil signatures. **D4Sign** runs its own document verifier. Signatures made with an ICP-Brasil certificate can be checked on ITI's validator, but its help center says "É comum que documentos assinados eletronicamente na D4Sign não sejam validados pelo sistema do ITI" (it is common for documents signed electronically on D4Sign, meaning without an ICP-Brasil certificate, not to be validated by ITI's system), and that Adobe flags its certificate because "o certificado da D4Sign não está nessa lista padrão" (it isn't on Adobe's default list). **Attest** puts the check inside the file. Every party downloads the same sealed PDF: the signed pages, with a "Signed with Attest" stamp on each signature and a seal line at the foot of every page, a certificate of completion, the audit trail up to completion and a "Verify it yourself, without us" page, with the full evidence, the original document and a standalone verifier attached inside. Drop the PDF on that verifier in any browser and it checks the original document against what every signer signed, each signer's passkey signature, Attest's anchored record on the Horizen public blockchain, and every page you see, which it re-makes from what was signed and compares byte for byte, with no Attest service involved. ## How signers sign On ZapSign, "Não é necessário ter uma conta ou cadastro para ser um signatário" (no account is needed to sign). An email code is included; as published on October 12, 2026, a ZapSign WhatsApp code costs R$0.50 on Profissional (included on Equipe), facial recognition R$1.50 and a full identity validation R$5.00. On D4Sign, a signer without an account enters their full name, CPF and date of birth, and the sender can add checks such as Pix, selfie, video selfie or D4Sign Score, which matches the signer against Denatran records; D4Sign Score, WhatsApp and SMS cost extra. On Attest, each signer approves with a **passkey**: a cryptographic key only the signer controls, unlocked with Face ID, Touch ID, Windows Hello or the device PIN. The passkey signs a statement naming the exact document, by its fingerprint, and everything the signer entered. There is no account or password to create, and signers never pay. ## Price in reais Attest's price is in US dollars: at the Banco Central do Brasil's PTAX selling rate of October 9, 2026 (R$4.9892 per dollar), $5 is about R$24.95. | | Attest | ZapSign (October 12, 2026) | D4Sign (October 12, 2026) | | ----------------------------- | ------------------------------------------ | ----------------------------- | ---------------------------------------------- | | Free | 2 documents, in total | 3 documents a month | 30-day trial | | 20 documents, monthly billing | About R$24.95 | Profissional: R$39.90 | Básico: R$39.90 | | 20 documents, yearly billing | Month to month only | R$29.90 a month, paid upfront | R$35.91 a month | | Extra documents | Wait for next month, or Pro at $49 a month | R$2.50 each | A larger tier (50 documents: R$59.90) | | API | Pro: $49 a month | From Equipe: R$69.90 a month | API Premium from Profissional: R$79.90 a month | ## When ZapSign or D4Sign is the better fit - **You want a free monthly allowance**: ZapSign's Individual plan sends 3 documents a month, free. - **You need ICP-Brasil signatures**: ZapSign issues certificates, and currently includes one with Equipe for new subscribers; D4Sign accepts signers' certificates at no extra cost. - **You need identity checks** such as CPF with the Receita Federal, facial biometrics, Serpro or Denatran matching. - **Your signers use WhatsApp**, and your team wants integrations (ZapSign lists HubSpot, Zapier, Make, Pluga and N8N) or contract management and AI (D4Sign Profissional). - **You want the product and support in Portuguese.** ## Who should choose Attest - **Businesses in Brazil with confidential agreements**, who want a service that can't read them: every Attest document is end-to-end encrypted in the browser. - **Anyone who wants proof that checks itself**, with the verifier inside the file. - **Small senders**: 20 documents a month for $5 (about R$25 at the PTAX rate of October 9, 2026), month to month. ## Starting on Attest Sign in with your email, set up your signing key with a passkey and a recovery phrase, upload a PDF of up to 8 MB, add your signers and place their fields. Your first 2 documents are free, in total. ## Questions people ask Do ZapSign or D4Sign end-to-end encrypt documents? ZapSign says it has no access to the content of your documents, and D4Sign says all data is encrypted end to end, as published on October 11, 2026. Neither describes where documents are encrypted or who holds the keys. Attest encrypts every document in your browser, locks its key to each party's own key, and stores it only as ciphertext it can't read. What do the free plans include? ZapSign's Individual plan sends 3 documents a month, free, and D4Sign offers a 30-day trial, as published on October 12, 2026. Attest's Free plan covers your first 2 documents, in total, each end-to-end encrypted and anchored on a public blockchain like every paid one, and its Signing plan is $5 a month for 20. How is an Attest signed copy checked in Brazil? With the open-source verifier attached inside it, in any browser, or by dropping it on attest.datahubz.com/verify, free and with no account. Its proof is each signer's own passkey signature and Attest's anchored record on a public blockchain; ITI's validator is for ICP-Brasil certificate signatures, which Attest signatures don't use. Is an Attest signature legally valid in Brazil? Brazilian law accepts electronic signatures outside ICP-Brasil for contracts between private parties when the parties admit the method as valid or the person the document is used against accepts it (MP 2.200-2/2001, art. 10, §2). A clause accepting the signing method helps, and acts that require a public deed, a notary or a qualified signature need more. This is general information, not legal advice. Which is cheapest for 20 documents a month? Attest, at $5 a month, about R$24.95 at the PTAX rate of October 9, 2026. ZapSign Profissional is R$29.90 a month paid yearly or R$39.90 monthly, and D4Sign Básico is R$35.91 a month billed annually or R$39.90 monthly, as published on October 12, 2026. ## Sources 1. [ZapSign: planos e preços](https://zapsign.com.br/precos/), ZapSign, read October 12, 2026 2. [ZapSign: sobre a ZapSign](https://zapsign.com.br/sobre-a-zapsign), ZapSign, read October 11, 2026 3. [ZapSign: como meus documentos ficam armazenados](https://clients.zapsign.com.br/help/como-meus-documentos-ficam-armazenados), ZapSign, read October 11, 2026 4. [ZapSign: valide documentos assinados](https://zapsign.com.br/funcionalidades/valide-documentos-assinados), ZapSign, read October 11, 2026 5. [ZapSign: validação de documento](https://zapsign.com.br/validacao-documento), ZapSign, read October 11, 2026 6. [ZapSign: assinatura eletrônica no padrão PAdES](https://clients.zapsign.com.br/help/assinatura-eletr%C3%B4nica-no-padr%C3%A3o-pades-o-que-%C3%A9-quais-n%C3%ADveis-existem-e-como-funciona-na-zapsign), ZapSign, read October 11, 2026 7. [ZapSign: normas ITI 2025, como a ZapSign se adaptou às novas regras](https://clients.zapsign.com.br/help/normas-iti-2025-como-a-zapsign-se-adaptou-%C3%A0s-novas-regras), ZapSign, read October 11, 2026 8. [ZapSign: a ZapSign está em conformidade com o ICP-Brasil](https://clients.zapsign.com.br/help/a-zapsign-est%C3%A1-em-conformidade-com-o-icp-brasil), ZapSign, read October 11, 2026 9. [ZapSign llms.txt](https://zapsign.com.br/llms.txt), ZapSign, read October 11, 2026 10. [D4Sign: planos e preços (prices from the page's embedded plan data)](https://d4sign.com.br/planos-e-precos), D4Sign, read October 12, 2026 11. [D4Sign home page (Zucchetti, 30-day trial)](https://d4sign.com.br/), D4Sign, read October 12, 2026 12. [D4Sign: assinatura eletrônica e digital](https://d4sign.com.br/assinatura-eletronica-e-digital), D4Sign, read October 12, 2026 13. [D4Sign: segurança da informação](https://ajuda.d4sign.com.br/seguran%C3%A7a-da-informa%C3%A7%C3%A3o), D4Sign, read October 11, 2026 14. [D4Sign: assinatura D4Sign não é validada no ITI](https://ajuda.d4sign.com.br/assinatura-d4sign-n%C3%A3o-%C3%A9-validada-no-iti-saiba-o-que-fazer), D4Sign, read October 11, 2026 15. [D4Sign: Adobe não reconhece a assinatura D4Sign](https://ajuda.d4sign.com.br/adobe-n%C3%A3o-reconhece-a-assinatura-d4sign-entenda-o-motivo), D4Sign, read October 11, 2026 16. [D4Sign: assinatura padrão simples](https://ajuda.d4sign.com.br/assinatura-padrao-simples), D4Sign, read October 11, 2026 17. [D4Sign: tipos de assinatura e validade jurídica](https://ajuda.d4sign.com.br/tipos-de-assinatura-e-validade-jur%C3%ADdica-na-d4sign), D4Sign, read October 11, 2026 18. [ZapSign: regulamento da promoção do certificado digital grátis no plano Equipe](https://zapsign.com.br/juridico/regulamento-promocao-certificado-digital-gratis-plano-equipe), ZapSign, read October 12, 2026 19. [D4Sign: assinando documento com certificado digital ICP-Brasil](https://ajuda.d4sign.com.br/assinando-documento-com-certificado-digital-icp-brasil), D4Sign, read October 12, 2026 20. [D4Sign Score: verificação avançada de assinaturas com Denatran](https://ajuda.d4sign.com.br/d4signscore-verifica%C3%A7%C3%A3o-avan%C3%A7ada-de-assinaturas-com-denatran), D4Sign, read October 11, 2026 21. [D4Sign: introdução à API](https://ajuda.d4sign.com.br/introdu%C3%A7%C3%A3o-%C3%A0-api-d4sign-leia-antes-de-come%C3%A7ar), D4Sign, read October 11, 2026 22. [PTAX dollar exchange rates, October 5 to 12, 2026, quotes through October 9 (Olinda open data API)](https://olinda.bcb.gov.br/olinda/servico/PTAX/versao/v1/odata/CotacaoDolarPeriodo%28dataInicial=@dataInicial,dataFinalCotacao=@dataFinalCotacao%29?@dataInicial='10-05-2026'&@dataFinalCotacao='10-12-2026'&$format=json), Banco Central do Brasil, read October 12, 2026 23. [Medida Provisória 2.200-2/2001 (ICP-Brasil), art. 10](https://www.planalto.gov.br/ccivil%5F03/mpv/antigas%5F2001/2200-2.htm), Presidência da República (Planalto), read October 11, 2026 24. [Lei 14.063/2020 (electronic signatures), compiled text](https://www.planalto.gov.br/ccivil%5F03/%5Fato2019-2022/2020/lei/l14063.htm), Presidência da República (Planalto), read October 11, 2026 25. [Código Civil (Lei 10.406/2002), compiled text, art. 108](https://www.planalto.gov.br/ccivil%5F03/leis/2002/l10406compilada.htm), Presidência da República (Planalto), read October 11, 2026 26. [Provimento CNJ 149/2023, Código Nacional de Normas (e-Notariado)](https://atos.cnj.jus.br/atos/detalhar/5243), Conselho Nacional de Justiça, read October 11, 2026 ## Read next - [Attest vs Clicksign](https://attest.datahubz.com/compare/attest-vs-clicksign) Attest vs Clicksign (Brazil) on encryption, ICP-Brasil, proof that needs no renewal and price, with Clicksign's plans as published on October 12, 2026. - [Electronic signatures in Brazil](https://attest.datahubz.com/legal/electronic-signatures-brazil) Brazilian e-signature law in plain language: MP 2.200-2/2001, Lei 14.063/2020, simple, advanced and qualified signatures, ICP-Brasil, notaries and proof. - [Can your e-signature company read your contracts?](https://attest.datahubz.com/guides/can-e-signature-company-read-your-contracts) Most e-signature services can decrypt the documents they store. Attest encrypts every document in your browser before upload, so it can't read them. - [Document signing](https://attest.datahubz.com/sign) Electronic signatures with a passkey: no account or password for signers, documents encrypted in the browser, and a signed copy anyone can verify. --- Source: https://attest.datahubz.com/compare/attest-vs-zapsign-and-d4sign