Caspian Office v1.221.7 client-side · private · free
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Install Caspian Office Add it to your home screen — full-screen, works offline.
Caspian Office / Organize PDF / Split PDF
Split PDF

Cut a PDF into separate files by clicking between pages.

Caspian Office

Every tool. One place.

A free, private, browser-based office toolkit. — tools that run entirely on your device — nothing is ever uploaded.

Files never leave your device Works fully offline No AI · no accounts · free
Drop a PDF here
or click to choose a file
Drop PDFs here to merge
or click to choose files · select multiple PDFs at once
Drop a PDF here
or click to choose a file
Drop a PDF here
or click to choose a file
Drop a PDF here
or click to choose a file
Drop a PDF here
or click to choose a file
Drop images here to make a PDF
or click to choose files · JPG, PNG and WebP supported · select multiple
Drop a PDF here
or click to choose a file
Drop a PDF here
or click to choose a file
Drop a PDF here
or click to choose a file
Drop a PDF here
or click to choose a file
Drop a PDF here
or click to choose a file
Drop a PDF here
or click to choose a file
Drop a PDF here
or click to choose a file
Drop a fillable PDF here
or click to choose a file · works with text fields, checkboxes, radio buttons and dropdowns
Drop a PDF here to redact
or click to choose a file · click and drag to cover sensitive content
A
Drop the original PDF
or click to choose
B
Drop the revised PDF
or click to choose
Load both PDFs to compare. The tool extracts text from each, then shows you what was added, removed, or kept. Works best on text-based PDFs (not scanned images).
Paste HTML markup or upload an .html file. Set the page size and margins on the right, then click Convert & Download. Works great for invoices, reports, certificates and styled documents.
Try a sample:
Drop an .html file here
or click to choose
Page size
Orientation
Margins
Quality
File name
Use your camera to capture pages. Position the document in view, hold steady, and press the big red button. Captured pages appear on the right — drag to reorder, click to delete. When you're done, click Build PDF.

Camera not started

Click below to start your camera. Your video stream stays in this browser — no images are uploaded.

Captured pages · 0
Pages you capture will appear here.
Drag to reorder.
Drop a PDF here to edit
or click to choose a file · add text, rectangles and highlights anywhere on the page

Add text

Drop images here
or click to choose files · JPG, PNG, WebP, BMP — as many at once as you like
Pick a type below, fill in the form, and your QR code appears live on the right. Customize colours and size on the right, then download as PNG or SVG.
Live preview — bytes

Your QR code will appear here.

Start typing in the form above.

Size
512
Error correction
Higher = more resilient to damage but larger code.
Margin (quiet zone)
2
Foreground colour
Background colour
For scannability, keep strong contrast between the two colours.
Drop an image here to crop
or click to choose a file · supports JPG, PNG, WebP, BMP
Drop an image here to resize
or click to choose a file · supports JPG, PNG, WebP, BMP
Checking for updates…
Reaching out to caspiantools.com to see if a newer version is available.
Library versions —
Settings Never checked
Check for updates on launch
Once per 24 hours. Sends a single request to caspiantools.com to compare versions — that request carries no file contents and no identifiers.

What's new

Caspian Office is updated frequently. Below is a running history of every release — every new tool, every fix, every improvement.

CURRENT VERSION · v1.221.7
v1.221.7 28 September 2026 Background remover
Background remover: the model really downloads once, and a Plain colour mode for logos
FixedThe AI model downloaded on every visit despite the “first use only” promise. The Background remover left its ~90 MB of model chunks to the browser’s ordinary HTTP cache, which drops them freely. They are now stored in a dedicated cache bucket that survives app updates, the runtime version is pinned so the model’s address never silently changes, and the service worker serves both from that bucket — so after one download the tool runs offline, including in the installed app. A Delete the stored model link above the tool frees the space if you ever want it back.
NewPlain colour mode. For logos, icons, signatures and scans on a single-colour background: the tool reads the background colour off the image edge and makes every pixel close to it transparent, with soft, de-fringed edges and no model download at all. Thin text and light shades — exactly what the AI model tends to eat — survive intact.
NewFine-tune the cut-out. A Keep more / Remove more slider under the result. In Auto mode it reshapes the model’s matte so faint parts of the subject (thin lettering, hair, glass) come back or leftover haze goes; in Plain colour mode it sets how far from the background colour still counts. Adjusting is instant — the model runs once per image and the cut-out is re-composited in the browser.
FixedA failed model load stuck until reload. The runtime memoised the failed attempt, so “Remove background” kept failing after a dropped connection. Each retry now starts a fresh session, and a corrupt cached chunk is purged and re-fetched automatically.
ImprovedThe download progress shows megabytes, the mode and slider positions are remembered, and the tool’s guide and every string are translated in all 12 languages.
By CaspianTools

Built for the community.

Caspian Office is a free, private, browser-based suite of everyday office tools. No uploads, no accounts, no ads. Your files never leave your computer.

Visit CaspianTools.com →

Install it on your device

Add Caspian Office to your phone or desktop for one-tap, full-screen, offline access — no app store, no account. On iPhone & iPad, we'll show you the two-tap "Add to Home Screen" steps.

Or keep it as a file

Use the download button in the header to save Caspian Office as a single HTML file that runs from your own device with no internet at all — a single tool on its own, one collection, or everything. A single tool is about 1.5 MB, small enough to email or carry on a USB stick.

Why this exists

Working with PDFs shouldn't mean uploading your private documents to a stranger's server. Yet that's how almost every "free" online PDF tool works — your file is uploaded, processed on someone else's machine, and you're asked to trust that it's deleted afterwards. Contracts, IDs, medical reports, work documents, family paperwork — none of that belongs on a third-party server you don't control.

We built Caspian Office on a different premise: your file should never leave your computer. Every tool you see here runs entirely inside your web browser, on your device. There is no server doing the work behind the scenes. There is no account to create. There is no usage limit. You can disconnect from the internet after this page has loaded and almost everything will still keep working. The exceptions are both in Speech to Text: its private on-device model is downloaded once from a CDN on first use (then cached, and it transcribes offline after that), and its optional browser live dictation mode uses your browser's own speech service, which sends that microphone audio to the browser maker. Every other tool — and Speech to Text's default on-device mode — keeps your data on your machine.

Two honest caveats. First, the hosted website at caspianoffice.io can use Google Analytics to count anonymous, aggregate usage (page views and which tools are opened) so we know what to improve — but it's off until you opt in via the cookie banner, and even then it never receives your files or their contents. The downloadable offline copy contains no analytics at all: that build is stripped of this script and still makes zero network requests. Our Privacy Policy has the full picture. Second, if you leave the "Check for updates on launch" toggle enabled on the Updates page (it's on by default), Caspian Office sends a single GET request to office.caspiantools.com/versions.json at most once every 24 hours, to see whether a newer version exists. That request carries no file contents and no identifiers. Turn it off in the Updates page if you'd rather check manually.

What you get

Private by design

Your files are processed in your browser. Nothing is uploaded. We literally cannot see your files — the website's analytics only count anonymous page views, never your documents.

Free, forever

No subscription, no premium tier, no watermarks on the output, no daily file limits. The tools are open and available to anyone who needs them.

Fast & offline-capable

Once the page is loaded, the toolkit runs offline (the only exception is the one-time download of the Speech to Text AI model). No round-trips to a server means everything happens at the speed of your own machine.

For everyone

Works on any modern browser, on any device — Windows, Mac, Linux, phone, tablet. No installation. No sign-up.

Take it with you

Download the whole toolkit — or just a single Collection (HSE, Developer, PDF Essentials and more) — as one self-contained HTML file. A Collection pack is far smaller and opens to just those tools, working fully offline. Nothing to install: email it, keep it on a USB stick, run it anywhere.

Our promise to the community

We made this because we needed it ourselves. We're a small independent studio, and we believe everyone — students, freelancers, small business owners, parents, healthcare workers, teachers, anyone — deserves access to honest, simple tools that respect their privacy. Not every problem needs a SaaS subscription. Some things should just work.

  • We will never charge you to use the tools on this page.
  • We will never upload your files anywhere. They stay on your device.
  • We will never show you ads, and we will never sell your data or your files.
  • We will keep adding tools as long as they're useful to the community.
  • We explain every tool right on the page — what it does, how to use it, and answers to common questions.

How it works under the hood

Caspian Office is built on a small set of trusted open-source libraries that run entirely in your browser. We didn't reinvent the wheel — we put a friendly, focused interface on top of mature, battle-tested code so anyone can use it without needing to understand what's under the hood.

pdf.js 6.2.108 Built by Mozilla. Renders every page thumbnail you see, and reads the structure of PDFs you open.
pdf-lib 1.17.1 Creates, edits, merges, splits, watermarks and rotates PDFs — directly in JavaScript, with no native dependencies.
JSZip 3.10.1 Bundles multiple output files (like split pages or exported images) into a single downloadable zip archive.
html2pdf.js 0.14.0 Turns on-screen documents — like the word processor and SWOT pages — into downloadable PDFs.
mammoth 1.12.0 Reads Microsoft Word .docx files and converts them to clean, editable content.
xlsx (SheetJS) 0.20.3 Opens and writes Excel spreadsheets entirely in the browser, powering the spreadsheet tools.
tesseract.js 7.0.0 On-device OCR (English, Turkish, German, French & Spanish) — extracts text from images and scans without anything leaving your device.
transformers.js 4.2.0 Runs OpenAI's Whisper speech-recognition model on your own device for the Speech to Text tool. The model downloads once, then transcribes locally — your audio is never uploaded.
kokoro-js 1.2.1 Runs the Kokoro-82M neural speech model on your own device for the Text to Speech tool's realistic AI voices. The model downloads once, then generates locally — your text is never uploaded.
lamejs 1.2.7 Pure-JavaScript LAME MP3 encoder — powers the MP3 export in the audio trimmer, converter, merger and Text to Speech, entirely in the browser.
mediabunny 1.50.8 Reads and writes MP4, MOV, WebM and MKV using the browser's own WebCodecs engine — the machinery behind the video trimmer, compressor, resizer, converter and audio extractor.
qrcode-generator 1.4.4 Generates QR codes locally for links, text and contact details.
DOMPurify 3.4.9 Sanitizes the HTML from imported Word documents before it's rendered, stripping any unsafe scripts or handlers.
Chart.js 4.5.1 Draws the bar, line, pie, radar and scatter charts in the Chart maker — rendered to a canvas entirely in your browser.
PptxGenJS 4.0.1 Writes the editable PowerPoint .pptx files exported from the Slides tool, assembling the Office Open XML package locally with JSZip.
marked 18.0.5 Parses Markdown into HTML for the Markdown editor's live preview and its PDF/HTML exports — rendered locally, then sanitised with DOMPurify.
JsBarcode 3.12.3 Draws the retail and product barcodes (Code 128, EAN, UPC, Code 39 and more) in the Barcode generator, as PNG or scalable SVG.
gifenc 1.0.3 Encodes GIFs entirely in the browser — it turns captured video frames into a looping GIF for the Video to GIF tool, and writes single-frame GIFs for the Image converter.
heic2any 0.0.4 Decodes Apple HEIC/HEIF photos (libheif compiled to WebAssembly) so the Image converter can turn iPhone pictures into any other format — entirely on your device.
imagetracer 1.2.6 Traces a bitmap into real vector shapes — the machinery behind the Image converter's PNG, JPG and photo-to-SVG conversion, with your own choice of colour count and detail.

These libraries are bundled with the app and cached by your browser, so the toolkit keeps working offline after your first visit. You can see the exact version of each — and whether a newer release is available upstream — on the Updates page.

Roadmap

Tools we plan to add next. Caspian Office stays 100% client-side — everything runs on your own device, and the rare tool that needs an AI model (like Speech to Text) runs that model locally too, never on a server. This list only includes things we can build reliably to run entirely in your browser.

    Who's behind it

    Caspian Office is built and maintained by CaspianTools, an independent software studio focused on practical, privacy-respecting tools for everyday digital work. We make developer utilities, productivity software, and small focused apps like this one. Three principles guide what we build: it should be private by design, useful by default, and free wherever possible.

    If Caspian Office saves you a few minutes, that's all the thanks we need. If you'd like to support what we do, the most meaningful thing you can do is share it with someone who'd find it useful — a friend, a colleague, a parent, a teacher. Word of mouth is how community tools survive.

    Caspian Office v1.221.7 · caspiantools.com · Made with care for the community

    These preferences are saved only on this device — nothing is uploaded. Pick them once and every tool starts with your choice.

    Units
    Metric or imperial — applies to the BMI, heat-index and drilling calculators.
    Default currency
    The currency new invoices, quotes and other money tools start with. Symbol only — no exchange rates.
    Paper size
    Page size for PDF and print exports across the document tools.
    Theme
    Light, dark, or follow your system. The tools themselves stay on a light page for now.
    My details
    Prefill your invoice, quote, business card, email signature and résumé — filled in once here.
    Logo
    Social links (optional)

    Privacy Policy

    Caspian Office is built so your files never have to leave your device. This page explains, plainly and honestly, exactly what does and doesn't happen with your data.

    Last updated: 24 June 2026

    Your files stay on your device

    Every tool on Caspian Office runs entirely inside your web browser, on your own computer or phone. When you open a PDF, image or document, it is read and processed locally — it is never uploaded to us or to anyone else. We operate no server that receives your files, and we have no way to see their contents. After this page has loaded you can disconnect from the internet and almost everything keeps working.

    What is stored on your device

    To remember your preferences and the work you have in progress, some tools save data in your browser's local storage — for example your theme choice, recent settings, and content you're actively editing (such as notes, a to-do list, or a diagram). This data lives only in your browser, on your device. We never receive it. You can clear it at any time from your browser's site-data settings, or by using each browser's "clear browsing data" feature for this site.

    Analytics & cookies (hosted website only)

    The hosted website at caspianoffice.io can use Google Analytics to count anonymous, aggregate usage — page views and which tools are opened — so we know what to improve. Analytics is off until you opt in: no analytics cookies are set unless you choose Accept on the cookie banner. If you accept, Google Analytics sets cookies (typically _ga and _ga_<id>) to measure visits, and we enable IP anonymisation. Analytics never receives your files or their contents.

    The downloadable offline copy of Caspian Office contains no analytics at all — that build is stripped of this script and makes zero network requests.

    The few times the browser does reach the network

    • Update check. If you leave the "Check for updates on launch" toggle on (it's on by default), Caspian Office sends a single GET to office.caspiantools.com/versions.json at most once every 24 hours to see whether a newer version exists. It carries no file contents and no identifiers. Turn it off on the Updates page to check manually.
    • Speech to Text. Its private, on-device model is downloaded once from a CDN on first use, then cached so it transcribes offline afterwards. Its optional browser live dictation mode uses your browser's own speech service, which sends that microphone audio to the browser maker — that mode is clearly labelled and entirely optional.
    • Web fonts in a few tools. The Image Editor and Slides tools can load optional fonts from Google Fonts; when used, your browser requests those font files from Google, which means Google sees the request and your IP address. Built-in, offline-safe fonts are always available as an alternative.

    What we never do

    • We never upload your files — they are processed on your device and stay there.
    • We never sell, rent or share your data, and there are no advertising trackers.
    • We never require an account — there is nothing to sign up for and no profile to build.

    Your rights & contact

    Because we don't collect personal data or hold any account, there is nothing of yours for us to look up, export or delete on our side — your data is already entirely in your hands. You can withdraw analytics consent at any time using the controls above, and clear all locally stored data from your browser settings.

    Questions, or a security issue to report? Email caspiantools@googlegroups.com (security researchers: see /.well-known/security.txt).

    Tool not built yet

    This tool is in the menu but the implementation hasn't been added yet. Ask Claude to build the next one — one tool at a time.

    build the Merge PDF tool next