Free · no accountNothing uploadedNo install

Free online tools that run in your browser

A growing library of small, sharp tools for media, text, code, documents, study and design. They open in a tab, do the job on your own device, and never ask you to hand over the file first.

No sign-up, everNo watermarks or limitsWorks offline once loaded

All floi tools, by category

Every tool floi has, and every one it is building, shelved by what you came here to do. Search it, filter it, or just read down the page. Nothing here is behind a menu.

17 tools ready to use · 20 more in build

Media & images

Video, images and audio. Your browser already ships a decoder for all three. These tools just give it a handle.

9 ready · 1 in build

Text & writing

Count it, convert it, compare it, clean it up. Nothing here needs to see a server.

2 ready · 3 in build
Word & Character CounterWords, characters, sentences, paragraphs and reading time, counted as you type.Open toolFree · in-browser
Case ConverterUpper, lower, title, sentence, camel, snake and kebab, in one pass.In build
Text Diff CheckerCompare two versions side by side and see exactly what moved, line by line or word by word.In build
Line Sorter & DeduplicatorSort, reverse, shuffle, number and strip duplicate or blank lines from a list.In build
Lorem Ipsum GeneratorPlaceholder copy by the word, sentence, paragraph or character, in classic Latin or plain English. Counts what it made.Open toolFree · in-browser

Developer

The everyday encode / decode / validate jobs, with the reassurance that a pasted token or key never left the tab.

2 ready · 4 in build
JSON Formatter & ValidatorPretty-print, minify, validate and explore a JSON payload as a collapsible tree. Errors are pinned to a line and a column.Open toolFree · in-browser
Base64 Encoder & DecoderText, files and data URIs, both directions, with UTF-8 handled properly.In build
Hash GeneratorSHA-1, SHA-256, SHA-384 and SHA-512 of text or a file, straight from the Web Crypto API.In build
UUID GeneratorCryptographically random v4 identifiers, one or ten thousand, generated locally.In build
Regex TesterMatch, highlight and explain a pattern against your own sample, with capture groups broken out.In build
QR Code GeneratorLinks, Wi-Fi, contacts and more, drawn in your own tab and saved as PNG or SVG. Static codes, so nothing expires.Open toolFree · in-browser

Documents & office

PDFs and spreadsheets, handled locally. The category where "upload your file to our server" is the least acceptable, and the least necessary.

2 ready · 4 in build
File TransferSend a file straight from one device to another, across any network. The file goes browser to browser, so it is never uploaded and never stored.Open toolFree · in-browser
Merge PDFCombine several PDFs into one and reorder the pages before you save.In build
Split PDFPull out a page range, or break a document into single-page files.In build
PDF to ImagesRender any page to PNG or JPG at the resolution you choose.In build
Images to PDFDrop a set of photos or scans and get one paginated PDF, with page size and margins under your control.In build
CSV to JSON ConverterConvert either way, with the delimiter detected, a preview table, and quoted fields handled properly.Open toolFree · in-browser

Education & study

Calculators, converters and study aids that load instantly and work offline.

1 ready · 4 in build
Flashcard MakerPaste a list to build a deck, study it with spaced repetition, and print it double-sided. Your deck stays in your own browser.Open toolFree · in-browser
Scientific CalculatorFull keyboard entry, a visible tape of what you typed, and no ads between you and the answer.In build
Unit ConverterLength, mass, area, volume, speed, temperature, data and time, in one field.In build
Percentage CalculatorPercentage of, increase, decrease and change, each with the working shown.In build
Pomodoro TimerWork and break intervals that keep running in a background tab, with no account to make.In build

Design & colour

Colour maths, contrast checking and palettes, in the place you are already working.

1 ready · 4 in build
CSS Gradient GeneratorLinear, radial and conic gradients with per-stop control. Copy the CSS, or save the same gradient as a PNG.Open toolFree · in-browser
Colour ConverterHEX, RGB, HSL, OKLCH and CSS names, converted live and copied in one press.In build
Contrast CheckerWCAG 2.2 ratios for text and UI, with the nearest passing shade suggested when a pair fails.In build
Palette GeneratorBuild a tint and shade ramp from one seed colour, interpolated in a perceptual space.In build
Image Colour ExtractorPull the dominant colours out of a photo and take them away as a palette.In build

Why a browser tool beats an upload form

Every tool here is built on something your browser already ships: its media decoders, a canvas, Web Crypto, the file APIs. That is not a limitation worked around; it is the entire design.

Private by architecture

Not "we promise not to look". On every tool here but one, there is no server that could receive your file, and you can prove it from the Network tab. The exception is file transfer, which sends your file to your other device and says on its own page exactly what it passes through.

Instant, even on huge files

Nothing waits in an upload queue. A multi-gigabyte video opens the moment you drop it, because it never moves off your disk.

Free without an asterisk

No account, no trial, no watermark, no daily cap, no "upgrade to download". Static files on a CDN cost almost nothing to serve, so nothing needs gating.

No install, any platform

No extension to trust, no app to update. Windows, macOS, Linux, ChromeOS, Android and iOS all get the same tool, because it is just a web page.

Keeps working offline

Once a page has loaded there is nothing left to call home to. Disconnect and the tools that work on your own files carry on exactly as before.

Keyboard-first and accessible

Single-key shortcuts drive the whole flow, focus order is real, and everything is labelled for a screen reader rather than left to a placeholder.

Frequently asked questions

What is floi?

A free library of small, single-purpose tools that run inside your browser tab instead of on somebody's server. Converting an image, formatting some JSON, pulling a frame out of a video, checking a colour contrast ratio. These are the everyday jobs you currently solve by searching, landing on an ad-covered page, and uploading your file to a stranger.

17 tools are live today and 20 more are named and in build. The whole directory is on this page.

Is it actually free, or free until I hit a limit?

Actually free. No account, no email, no trial, no watermark, no daily cap and no paid tier waiting behind a "download" button. floi is static files on a CDN. Serving it costs almost nothing, so there is nothing that needs to be gated to pay for it.

Do my files get uploaded anywhere?

No. Your browser does the decoding, the canvas work and the encoding locally, and even ZIP archives are assembled inside the page. You can open your developer tools, watch the Network tab, and confirm that a file you drop in generates no outbound request at all.

That page said a future tool might genuinely need a server, and that it would say so plainly. One now does. File transfer sends a file from one of your devices to another, and two browsers cannot open a direct connection without swapping a few kilobytes of network addresses and encryption keys first. A ten minute room passes those two blobs between them and is then destroyed. It never receives a filename or a byte of a file, and the tool page explains the whole arrangement.

What kinds of tools are here?

Media & images, Text & writing, Developer, Documents & office, Education & study, Design & colour. The list is meant to keep growing. The rule for what gets built is simply whether a browser can do the job honestly and well; if it can, it belongs here rather than behind an upload form.

Why does it matter that the tools run in the browser?

Three practical reasons, beyond the privacy one. It is faster, because a multi-gigabyte file never waits in an upload queue. It works on files that are too big or too sensitive to send anywhere. And it keeps working when the connection does not. Once a page has loaded, most tools run offline.

Do I need to install anything?

No. There is no extension, no desktop app and no sign-up. Every tool is a web page: open it, use it, close it. It works on Windows, macOS, Linux, ChromeOS, Android and iOS. If the browser can open the file, the tool can work on it.

Does everything work on a phone?

Almost everything. The one current exception is live screen capture, which depends on a desktop-only browser API. Anything that is desktop-only says so on its own page rather than failing quietly when you get there.

What are the "in build" tools, and when do they land?

They are the tools already designed and queued, listed by name so you can see where floi is going rather than being told "more coming soon". They are not links, because there is nothing behind them yet. A card becomes a link on the day the tool actually works. No dates are promised, because a promised date on a free project is just a broken one waiting to happen.

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