Sending a password over email, pasting an API key into Slack, or uploading a sensitive file to a general-purpose cloud drive all share the same quiet risk: the content sits there in plain text, in someone else's inbox or storage, long after the moment it was actually needed. It doesn't get deleted, it doesn't expire, and if that email account or cloud account is ever breached, everything you ever sent through it goes with it. The tools below exist specifically to close that gap — encrypting what you send so that even the service running it can't read the contents.
The short version
The short version: for a one-time password or API key, use InPrivy — a self-destructing link beats a Slack message every time. To hand someone a file directly without a cloud account, croc sends it computer-to-computer, encrypted, from the command line. For messaging that doesn't even know who you are, SimpleX Chat drops the phone number entirely. If you need actual cloud storage without a single company holding your files, TransferChain splits and scatters them across providers. For notes and docs the server itself can't read, there's markdown.gg; for a full offline-first productivity suite with encrypted chat built in, BlackBear. And if the sensitive thing is an AI conversation rather than a file, Tinfoil runs it inside hardware that's provably sealed off — while Ubiq Security handles the enterprise problem of finding and locking down sensitive data you didn't even know you had scattered across your systems.
InPrivy — one-time links for passwords and API keys
InPrivy replaces the habit of pasting a password or API key into an email or chat message — where it sits forever — with a link that self-destructs the moment it's opened, or after a set time. It's AES-256-encrypted, aimed at teams (law firms, accountants, IT companies) that need to hand off sensitive text or files without leaving a permanent record.
Pricing: a one-time lifetime license rather than a subscription — €49 for Solo (10GB), €129 for Business (30GB), with a 20-day trial.
Forces: no recurring bill, ISO 27001 certified with servers in Germany (useful for EU data residency), an API for programmatic secret sharing, and notifications when a link is opened.
Limites: free tools cover the basic case if you don't need the compliance or branding features, there's no public pricing page to compare at a glance, and it's a lot less known than the giants of the password-manager space.
Pick InPrivy if: you regularly need to hand off credentials or sensitive text to clients or teammates and want a paid-once, EU-hosted tool rather than another monthly subscription.
croc — send a file directly, no cloud account needed
croc skips the cloud middleman entirely: you run one command, get a short memorable code phrase, tell the other person the phrase, and the file transfers directly between the two computers — encrypted the whole way, with no upload-then-download round trip and no account required on either end.
Pricing: free and open-source (MIT license), including a self-hosted relay option for teams that want transfers to stay entirely in-house.
Forces: mature since 2017 with roughly 38,300 GitHub stars, end-to-end encryption by default via PAKE, resumable transfers, works over Tor, and even generates QR codes for phone-to-computer sends.
Limites: command-line only (no native GUI), both sides need the tool or its web client installed, and it's a harder sell to a non-technical recipient than a link they can just click.
Pick croc if: you're a developer who needs to move a file to a colleague right now without waiting on cloud sync, and you're comfortable with a terminal.
SimpleX Chat — messaging with no identity to leak
Most privacy messengers, Signal included, still tie your account to a phone number — which means the app, or anyone who compromises it, can at least see who's talking to whom. SimpleX Chat removes that identifier entirely: every conversation gets its own private, disposable connection instead of a persistent account, so there's no central identity to track in the first place.
Pricing: free, open-source (AGPL-3.0), with native apps for iOS, Android, desktop and a CLI/terminal client.
Forces: no phone number, username or account ID required; double-ratchet end-to-end encryption with post-quantum resistance; an invitation-link-only contact model that blocks spam by design; and, since version 6.0, private message routing that the project says protects metadata more strongly than Signal, Matrix or Session.
Limites: a much smaller user base than Signal, fewer independent security audits published, added friction when adding contacts since it's invite-links-only, and a rougher interface for non-technical users.
Pick SimpleX Chat if: you want messaging where the provider genuinely cannot build a social graph of who you talk to, not just encrypted content.
TransferChain — cloud storage no single company can read
Regular cloud storage means trusting one company to hold the only readable copy of your files. TransferChain encrypts files on your own device before they ever leave it, splits them into pieces, and scatters those pieces across several different cloud providers — so even if one provider were hacked or subpoenaed, nobody holds a complete, readable file except you.
Pricing: a free Teams plan covers 5GB for up to 3 users; paid tiers scale by storage (from $20/100GB) and seats (from $1/seat), with 20% off annual billing.
Forces: client-side, zero-knowledge encryption; built for regulated industries (healthcare, insurance, defense) needing ISO 27001 and GDPR-aligned storage; and a genuinely usable free tier for small teams.
Limites: paid-tier pricing beyond the free plan isn't published in detail, the distributed-storage model is more complexity than a solo user needs, and it's less well-known than incumbents like Tresorit.
Pick TransferChain if: your team handles regulated data and needs actual cloud storage — not just one-off transfers — with no single vendor able to read the contents.
markdown.gg — notes the server can't read
A hosted markdown editor or pastebin usually means trusting the provider not to read what's sitting in plain text on their server. markdown.gg encrypts everything client-side with AES-GCM before it's ever transmitted, so the backend only ever stores and serves blobs it's mathematically unable to decrypt itself.
Pricing: free and open-source (MIT license) — self-hostable, with SQLite for development or PostgreSQL for production.
Forces: a genuinely nice side-by-side Monaco editor with live preview, LaTeX/KaTeX math rendering, and full GitHub Flavored Markdown support (tables, task lists, strikethrough); shares can be updated without generating a new link.
Limites: far less known than an established tool like HackMD, self-hosting requires some technical setup, and version history is more limited than a full collaborative editor.
Pick markdown.gg if: you want to share technical notes or docs where the hosting service itself is cryptographically locked out of reading them.
BlackBear — an offline-first suite with encrypted chat built in
Most people's toolkit is a pile of separate cloud accounts — a notes app, a spreadsheet app, a messenger — each sending data to a different company's servers. BlackBear bundles notes, docs, spreadsheets, calendar, tasks and end-to-end encrypted chat with voice/video calls into one app that works fully offline by default, with optional encrypted sync across devices.
Pricing: free for full local/offline use; Cloud sync is $2/month (10 devices, 5GB) or $5/month for Cloud Pro (25 devices, 50GB).
Forces: genuinely unusual for a productivity suite — encrypted messaging and calls live alongside notes and docs, not in a separate app; an AI companion (Pax) supports bring-your-own-API-key instead of a black-box model; over 100 integrations.
Limites: the ecosystem is far less mature than Notion or Google Workspace, each individual module is shallower than a dedicated specialist tool, and Teams/Enterprise plans aren't available yet.
Pick BlackBear if: you want to replace several separate cloud subscriptions — including your messaging app — with one local-first, optionally encrypted-sync suite.
Tinfoil — AI chat inside a provably sealed box
Using a typical AI chatbot or API means trusting the company behind it not to look at your conversations — a promise with no way to verify. Tinfoil replaces that promise with hardware proof: your data is processed inside a sealed, encrypted enclave that even Tinfoil's own engineers can't see into, and you can cryptographically verify the seal yourself before sending anything.
Pricing: Private Chat is $20/month, the Private Inference API is billed by usage, and Enterprise is quote-based.
Forces: open-source confidential computing (AMD SEV-SNP / Intel TDX plus confidential-computing-capable NVIDIA GPUs), an OpenAI-compatible drop-in API, client-side verification tools so the privacy claim is checkable rather than marketing, and — notably — the only platform currently offering multi-GPU confidential computing.
Limites: costs more than a standard AI subscription, there's real performance overhead from the confidential-computing layer, and the ecosystem is younger than established AI providers.
Pick Tinfoil if: you need to run AI chats or API calls on data you legally or contractually can't expose to a normal provider, and you want that guarantee to be verifiable, not just promised.
Ubiq Security — find and lock down data you didn't know was exposed
Most companies don't actually know where all their sensitive data lives — it's scattered across databases, warehouses and applications that grew organically over years. Ubiq Security starts by finding that data, then maps exactly who or what system can reach it, before deciding how to lock it down with encryption, tokenization or masking.
Pricing: enterprise, quote-based only — no self-serve tier.
Forces: identity-driven, zero-trust access controls; 46+ integrations spanning databases, warehouses, identity providers and APIs; plugs into an existing IAM setup (Okta, Azure, AWS) instead of requiring a separate access layer.
Limites: no public pricing, limited self-service documentation, and implementation at real scale is genuinely complex.
Pick Ubiq Security if: you're past the point of manually tracking where sensitive data lives across your company's systems and need discovery plus enforcement, not just another encryption library.
| Tool | What it protects | Starting price | Best for |
|---|---|---|---|
| InPrivy | Passwords, API keys, short text | €49 one-time | Sending a secret once, no subscription |
| croc | Files, direct transfer | Free | CLI-to-CLI file transfer, no cloud |
| SimpleX Chat | Messages, identity/metadata | Free | Messaging with no account to trace |
| TransferChain | Cloud-stored files | Free (5GB/3 users) | Regulated-industry cloud storage |
| markdown.gg | Notes and docs | Free (open-source) | Technical notes the server can't read |
| BlackBear | Notes, docs, chat, calls | Free (Cloud from $2/mo) | Replacing a whole cloud-app stack |
| Tinfoil | AI chats and API calls | $20/mo | Verifiably private AI usage |
| Ubiq Security | Enterprise data at rest | Quote-based | Finding and locking down unknown exposure |
None of these solve the same problem, which is exactly the point — "encryption" isn't one product, it's a property you can add to whatever you're already doing: sharing a secret, sending a file, chatting, storing data, or running AI workloads. Pick based on what's actually leaking today, not the tool with the most name recognition.