Free Tools That Run In Your Own Browser
No account, nothing uploaded Each one does a job we kept being asked for, and each one runs entirely in your browser tab. Your file is read on your own machine and never leaves it, which matters when the file is a client list, a bank statement or a folder of filled forms.
Most of this is paid elsewhere Nearly every one of these jobs is sold as a subscription somewhere, and the free versions stop at five hundred rows because they are front ends to a paid API. These go further than the paid ones in the places that matter: no caps, no sign up, and checks the paid tools do not run at all.
Built to be checked, not believed Every one of these pages says what it was tested against and how many checks it runs, and the numbers printed on each page are bound to the code behind them by a test. Where a tool cannot be sure of something, it says so instead of guessing.
Bulk Invoice Generator
Drop a spreadsheet of billing rows and get finished invoices, each with its VAT or GST treatment worked out on its own: EU reverse charge under Article 196, the UK construction reverse charge under section 55A, and the Indian split into CGST and SGST or IGST. The numbering is audited across the batch for duplicates and gaps, and every invoice comes with an e-invoice XML checked against the European standard.
Webhook Signature Verifier
Paste a webhook request and its secret and find out whether the signature matches. When it does not, the page tries thirteen body shapes and four secret forms and names what changed, which is usually a re-serialised body or a secret read the wrong way. Six providers' real schemes, verification code for five languages, and a correctly signed curl for local testing.
Merge and Join CSV Files
Join files on a key or stack them on top of each other. Fuzzy matching with scores, composite keys, seven ways of normalising a key, and unmatched rows downloadable on their own. It also runs each setting and tells you how many more rows a different one would match, which is the part nothing else does.
Cron Expression Generator
Build a cron expression and see the next runs in any of 418 timezones, with every run that daylight saving deletes or repeats named. Six dialects with conversion warnings, a why-did-it-not-run explainer, paste-ready manifests and clash checking against the jobs you already have.
JSON to Excel
Every nested array becomes its own sheet, carrying the key of the row it belongs to, so nothing is flattened into a wall of columns. Typed cells, Excel limit guards, a path picker for API envelopes, and a button that rebuilds the original JSON out of the workbook to prove nothing moved.
Address Splitter
Splitting an address into columns is guessing, and every tool in this category guesses. This one counts afterwards and tells you when the count does not come out. 136 countries and 65 languages in one file, each coming back out on its own, with no row limit.
Bank Statement Converter
Converting a statement is the easy half. Knowing whether a row went missing on the way is the half that costs you an evening. Every line is checked against the running balance the bank printed next to it, so a conversion that went wrong says where, and usually what happened.
PDF Form Data Extractor
Drop in a folder of filled PDF forms and every text box, tick, radio button, dropdown and list comes out as a row per form, ready for Excel. It happens inside the browser tab, so nothing is uploaded anywhere.
Product Title Character Counter
Six marketplaces at once, and it tells you where each number came from. Amazon cut the product title to 75 characters and moved the rest into a new field; plenty of counters still say 200. Emoji counted properly, and the byte figure that decides whether backend search terms fit.
What these have in common
- Nothing is uploaded. The work happens in your browser tab. There is no upload endpoint and no server waiting to receive anything, and you can disconnect after the page loads and carry on.
- No account and no row limits. The free tools in these categories usually stop at five hundred rows because they are front ends to a paid API. These run on your own machine, so your machine is the only limit.
- No libraries in the page. The browser already has what these need, which is also what makes the privacy claim checkable: there is no third-party script to audit.
- Limits stated early. Where a tool will not handle something, the page says so beside the upload box rather than letting you find out after it has failed.
- Corrections welcome. A file one of these handles wrongly is the most useful thing anyone can send us. Take the names out first, the shape is enough.
Need one of these wired into your own system?
These are the standalone versions. The same engines run inside client systems as scheduled jobs, API endpoints and back-office workflows: statements converted on arrival, invoices built from a billing table every month, forms extracted straight into a database. If one of these does most of what you need but not all of it, that gap is usually a short piece of work.