The ad-riddled "free online tools" sites people paste sensitive text into and upload confidential PDFs to - OmniTools replaces that whole ecosystem with one self-hosted app. It bundles 50+ utilities behind one clean React/TypeScript interface: image tools (resize, convert, crop, edit), video and audio tools (trim, reverse, convert), PDF tools (split, merge, edit), text and list utilities (case converters, formatters, shufflers), plus date/time, math, and data-format helpers for JSON, CSV, and XML. The architectural decision that makes it trustworthy is that all file processing happens entirely client-side in the browser - the server only serves static assets, and nothing you process ever leaves your device. That design has a pleasant side effect: the host needs almost no resources (people run it on a Raspberry Pi Zero), because your browser does the work while the server just delivers files. The Docker image is a remarkable 28 MB, making it one of the fastest apps to deploy and cheapest to keep running. There are no ads, no tracking, no accounts, and no upload limits. With multi-language support and an MIT license, it works equally well as a personal toolbox or a team-wide internal utility portal - one URL that replaces a bookmark folder full of questionable converters. Actively developed with 50 contributors and 9,500+ GitHub stars.

Adobe Acrobat and Smallpdf, answered by a self-hosted Java web application: Stirling PDF processes every file with its 60+ tools on your own server and deletes it after the task completes. Nothing is uploaded to a third party, which is the whole point for contracts, invoices, and medical records. The toolbox covers page operations (merge, split at page numbers or scanned dividers, rotate, reorder, crop, extract), conversion in both directions between PDF and Word, Excel, PowerPoint, images, HTML, and Markdown, OCR that turns scans into searchable PDFs via Tesseract/OCRmyPDF (including PDF/A archival conversion), and security tools for passwords, permissions, watermarks, signatures, and true UI-driven text redaction. A built-in viewer handles annotation, drawing, and text or image insertion, and V2 added stateful processing - upload once, chain multiple tools - plus undo/redo history. For automation, nearly every tool has a REST API endpoint, no-code pipelines combine operations into custom logic chains, and watched folders process files automatically. Enterprise deployments get SSO, user management, and audit logging; the interface ships in 40+ languages. With 84K+ GitHub stars it is the most popular PDF tool in self-hosting, replacing $20/month Acrobat subscriptions with flat infrastructure cost.

Send a document, receive a PDF: Gotenberg is a Docker-based, stateless HTTP conversion API trusted in production by thousands of companies and adopted by notable open-source projects. Send files as multipart/form-data, get a PDF back; Chromium, LibreOffice, and fonts are the container's problem, not yours. Headless Chromium handles URLs, HTML templates, and Markdown with pixel-perfect browser rendering: it executes JavaScript, loads web fonts, waits for network idle, a JS expression, or a DOM selector before rendering SPAs, and accepts injected cookies and HTTP headers for authenticated pages. LibreOffice converts 100+ office formats - .docx, .xlsx, .pptx, and legacy formats - with page-range extraction and PDF/A archival conformance. Built-in PDF engines round out the pipeline in every image variant: merge, split, rotate, flatten, encrypt, watermark, stamp, read/write metadata and bookmarks, plus Factur-X/ZUGFeRD e-invoicing and PDF/UA accessibility compliance. Screenshots of URLs and HTML come from the same endpoints. Zero-transfer pipelines stream files directly between S3, MinIO, or GCS presigned URLs and Gotenberg, bypassing your application entirely, and webhooks enable async processing. Statelessness means horizontal scaling is trivial - run as many replicas as your conversion volume demands. Three image variants (full, Chromium-only, LibreOffice-only) trim the footprint to what you actually use.

Merge, split, compress, convert, edit, annotate, redact, OCR, and sign PDFs - BentoPDF packs over 130 tools into a privacy-first toolkit that runs entirely in the browser through WebAssembly. Files are never uploaded - processing happens in browser memory on the user's machine and disappears when the tab closes, which makes the tool GDPR-clean by architecture and safe for financial, legal, and internal documents. The engine combines WASM builds of PyMuPDF, Ghostscript, and CoherentPDF; Tesseract handles OCR with searchable text-layer output; Office conversions cover Word, Excel, and PowerPoint; and digital signatures use X.509 certificates (PFX/PEM) with the private key staying on the client. Because there is no server-side processing, deployment is a static-file exercise: a single Docker container, or any static host. A dedicated self-hosted build strips the marketing pages while keeping every tool, and air-gapped deployments are first-class - an automated script bundles the WASM modules, OCR language data, and fonts for fully offline networks. No accounts, no limits, no watermarks; TypeScript and Vite under the hood.

Receipts, contracts, and letters that arrive as pixels rather than text: Papermerge is a document management system built specifically for scanned documents. Upload a PDF, TIFF, JPEG, or PNG and OCR runs automatically, with a real-time status indicator beside the document title; under the hood it drives OCRmyPDF and Tesseract, supporting 130+ languages and producing a new document version with a selectable, searchable text layer you can download. Full-text search runs across everything, with multiple search-engine backends (Xapian by default). The interface deliberately mimics a modern desktop file browser: dual-panel commander, drag and drop, hierarchical folders, and colored tags on documents and folders. Page management fixes what scanners get wrong - delete blank pages, rotate, reorder, merge, extract, and move strayed pages between documents, powered by PikePDF. Document types act as categories, each with its own custom metadata fields, so invoices carry vendor and amount while contracts carry parties and dates. Versioning preserves every state of a document. Multi-user support includes groups, group ownership, permission management, and document/folder sharing between users and groups, and an OpenAPI-compliant REST API automates ingestion from scanners or scripts. Apache-licensed, ideal for long-term digital archives.

A pile of paper becomes a searchable digital archive under Paperless-ngx, the community-maintained document management system. The pipeline is what makes it work: drop a file into the consumption folder (or let it poll an email inbox), and a worker hashes it for duplicate detection, routes it by type, runs OCRmyPDF with Tesseract (100+ languages) on anything without a text layer, and produces an archivable PDF/A with invisible selectable text embedded - so Ctrl+F works on your scans. Then the smart part: a scikit-learn classifier (TF-IDF plus multi-label prediction) trained on your own tagged documents automatically assigns tags, correspondents, and document types to new arrivals, alongside rule-based exact, keyword, and regex matching for deterministic cases. Full-text search includes relevance ranking, match highlighting, autocomplete, and "more like this" similarity search. Apache Tika integration extends consumption to Word, Excel, PowerPoint, and LibreOffice formats. The Django/Angular app adds custom fields, saved views on a customizable dashboard, bulk editing, workflow automation triggered on upload or matching, shareable public links with expiration, and a robust permissions system with per-document access control. Metadata lives in PostgreSQL with Redis-queued Celery workers processing documents in parallel. Your tax records, invoices, and contracts stay on your server - searchable in seconds, never in someone else's cloud.

Convert paper archives, email attachments, and PDF records into an organized digital repository with Docspell, an open-source document management system that automates optical character recognition, metadata extraction, and full-text search. Users can ingest receipts and invoices through network scanners, monitored IMAP email mailboxes, mobile uploads, or drag-and-drop browser tools. The background processing pipeline executes optical character recognition via Tesseract, enhances image contrast with unpaper, and extracts text from Word documents and PDFs. Machine learning algorithms analyze document syntax to predict correspondents, suggest relevant organization tags, and identify due dates automatically. Team members can search their entire filing cabinet using complex Boolean queries and full-text indexing powered by Apache Solr or PostgreSQL. Administrators can configure multi-user collectives with isolated permissions, define custom metadata attributes, set up webhooks, and share time-limited document download links. Users can also merge multi-page scans, track processing job queues, and export curated document collections for tax filings or legal audits. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. GNU AGPL v3.0 licensed.

Somewhere between the shoebox and the inbox, Papra keeps receipts, warranties, and leases in a self-hosted archive you can actually search. Upload a photographed receipt and built-in OCR reads its text, so a search for the store name finds it later. Searches combine name:, content:, tag:, created:, and has: filters with AND, OR, NOT, and parentheses, and any query can be saved as a sidebar view. Tagging rules label uploads by name or content and can be applied to documents already stored. Optional AI auto-tagging works with a cloud provider or a local model such as Ollama. Custom properties add searchable typed fields such as text, number, date, yes or no, and select. Organizations keep a household's or a team's archive apart, with owner, admin, and member roles. Share links let outsiders open a document without an account, with optional passwords and expiry dates, and each link can be switched off. Forward an email to a generated address, or drop files into a watched folder, and documents arrive without opening the app; both are opt-in. Deleted files wait 30 days in the trash, and optional encryption protects stored files. Sign in with email, GitHub, Google, or a custom OAuth2 provider, and script the archive through the API, SDK, CLI, or webhooks. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPL-3.0 licensed.

Every scan and PDF you drop into Teedy becomes searchable text in a self-hosted document archive, filed by nested tags instead of folders. OCR reads images in more than twenty languages, and the search box offers suggestions and highlights matches, even inside ODT, DOCX, and PPTX files. Video files are supported as well. Each record carries Dublin Core fields plus custom metadata of your own design, with comments and earlier file versions attached. When a document needs a second pair of eyes, workflow steps with assigned reviewers move it along in order until someone signs off. Pull in EML emails, let the server poll an inbox, or point the bulk importer at a whole folder, and incoming paperwork needs no manual filing. Share a single document through a public link, or keep it behind user and group permissions with a storage quota for each person. LDAP and two-factor authentication guard sign-in, 256-bit AES encryption protects stored files, and an audit log records who changed what. Webhooks alert other services, a documented REST API lets scripts take part, and an Android client carries the archive on a phone. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. GPL-2.0 licensed.

Mayan EDMS stores, classifies, and retrieves millions of documents with automatic OCR, workflow automation, and audit-ready access controls that organizations have relied on for over a decade. Tesseract integration extracts searchable text from scanned PDFs and images in over 100 languages, transforming paper archives into instantly queryable digital collections without manual data entry. The workflow engine routes documents through approval chains using configurable state machines that trigger notifications, enforce retention policies, and maintain complete audit trails for regulatory compliance. Version tracking preserves every revision with full diff capabilities, while GnuPG digital signatures provide cryptographic proof of authenticity and tamper detection for sensitive records. Role-based permissions combined with object-level ACLs and LDAP integration ensure documents remain visible only to authorized users, down to individual file granularity. Full-text search powered by Whoosh or ElasticSearch handles advanced queries across massive document stores with faceted filtering and relevance ranking. The Django REST Framework API enables programmatic upload, metadata extraction, and workflow triggering from external systems. Beyond simple folder hierarchies, metadata schemas, document types, tags, and cabinet structures provide multi-dimensional classification tailored to how your organization actually works. Background processing through Celery handles OCR, conversion, and preview generation asynchronously, keeping the web interface responsive under heavy ingest loads.

PdfDing turns a scattered folder of PDFs into a proper library you can read, annotate, sign, and share from any browser. The viewer remembers exactly where you stopped in every document, so a manual opened on your desktop resumes mid-page on your phone, and progress bars in the library show how far you have read at a glance. Workspaces and collections group related documents, multi-level tags classify them, and starring, archiving, and bulk actions keep even a large archive tidy. Inside the viewer you can add text, highlights, and freehand drawings, then review and export your highlights and comments from dedicated sections and attach Markdown notes to a document. A signature you create once is stored on your server and waits for you on every device, ready to drop onto contracts and forms. Sharing a collection or a single PDF takes a link or a QR code, with optional access control over who can open it and for how long. Accounts are protected by OIDC single sign-on and two-factor authentication with TOTP or WebAuthn, and dark mode, an inverted color mode, and multiple layouts keep long reading sessions comfortable. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPL-3.0 licensed.

Document-generation code is the worst kind of code in your backlog - Carbone kills it. Its insight is separating design from data - templates are ordinary office documents (DOCX, ODT, XLSX, PPTX, HTML, even custom XML) built in LibreOffice, Microsoft Office, or Google Docs, with mustache-like markers such as {d.companyName} typed directly into the text. Send a template plus JSON from your existing APIs to the HTTP API, and Carbone returns the finished document - exported as-is or converted to PDF, XLSX, CSV, HTML, PNG, EPUB, and more via its integrated LibreOffice converter (Chromium and OnlyOffice engines are also supported for HTML-fidelity and office-format conversions). The template language goes well beyond substitution: loops over arrays render dynamic table rows, filters and aggregations run inside the document, and built-in formatters handle dates, numbers, currencies, timezones, and locales, with custom JavaScript formatters when needed. One template serves multiple languages through translation markers with auto-maintained translation files. The XML-agnostic engine means anything your document editor can design - pagination, headers, footers, nested tables, charts - survives generation intact, and Carbone guarantees no breaking changes in template syntax. Node.js-based, fast via multi-threaded LibreOffice conversion. The invoices, contracts, and reports your product owes its users become template edits, not sprints.

Born at Brazilian media giant Globo.com, Thumbor answers imaging CDNs like Imgix and Cloudinary with an HTTP service where every image variant is just a URL. Ask for /300x200/smart/your-image.jpg and Thumbor fetches the original, crops and resizes on demand, and caches the result - one source file, unlimited renditions, no batch pre-generation pipeline. The "smart" in the URL is the signature feature: OpenCV-based face detection finds people in the frame and crops around them (no more thumbnails with severed heads), and when no faces exist, feature detection finds visually important corners and computes a weighted center of mass as the focal point. Beyond cropping, a chainable filter pipeline handles brightness, contrast, grayscale, blur, red-eye removal, rounded corners, rotation, watermarks, and format conversion with quality control - applied in order via URL segments. All common image formats work out of the box, and every layer is pluggable: loaders (HTTP, local, S3), storages and result storages (local, S3, Ceph, and community backends), engines, optimizers, filters, and even custom detectors, with the awesome-thumbor list cataloging the ecosystem. URL signing prevents abuse of your processing capacity. Integrations exist for Django, Rails, Node, WordPress, and most frameworks. MIT-licensed, battle- tested for over a decade.

Fifty-plus image processing tools in a single Docker container, with no Redis, no Postgres, and no external dependencies: SnapOtter is a self-hosted image toolkit. The everyday operations are all here: resize, crop, compress, watermark, vectorize, meme generation, GIF creation, and format conversion spanning 55+ input formats (including 23 camera RAW formats) to 14 output formats. What sets it apart is the local AI layer: background removal, photo upscaling and restoration, object erasing, face blurring, OCR, and canvas expansion all run on locally hosted models, so no image ever leaves your server - a hard guarantee that cloud tools like remove.bg or Canva can't make. Optional NVIDIA GPU support accelerates those AI tasks substantially when hardware is available, but everything works on CPU. A built-in layer-based editor handles composition work directly in the browser, and screenshot beautification turns plain captures into polished visuals with backgrounds, shadows, and padding - useful for docs and marketing alike. Batch operations process unlimited images simultaneously, and the full REST API with OpenAPI documentation exposes every tool for pipelines and automations: thumbnail generation on upload, bulk RAW conversion, automated watermarking. For teams processing sensitive imagery or anyone tired of per-image SaaS pricing, SnapOtter replaces a stack of subscriptions with one private container.