Data cleaning tool that shows you every change

Drop in a messy CSV. Every duplicate, broken date and mangled character comes back as a line you approve or reject, one at a time.

Reading CRM contact export

Clean a file Drop a CSV, or browse. Up to 5MB.

Row and column Proposed change Your decision

Pick a sample above, or drop a file

Every proposed change is listed here before anything is written.

-- rows scanned

-- duplicate clusters

-- date formats

Runs in your browser. Your file never leaves your computer.

Open the full review

01The file you were sent

You already know what is wrong with it

Nobody needs a lecture on data quality. They need the four things below to stop happening in the file they have to use this afternoon.

The same customer, four times

Acme Corp, Acme Corp., Acme Corporation and ACME CORP are one account.

Three date formats, one column

04/03/2026, 4-Mar-26 and 46085 all mean the same day, and none of them sort.

Postcodes missing a zero

02139 became 2139 the moment the file went through a spreadsheet.

Names turned into wreckage

Muñoz arrived as MuÃ±oz, and the person it belongs to will notice.

02What you get out of it

Three things change the day you clean the file

Stop mailing the same person twice

Fuzzy matching across name, company and email finds the duplicates an exact match leaves behind.

Fuzzy duplicate clusters

Make the totals tie out

Dates become ISO 8601, currency written as text becomes a number, and the leading zeros come back.

Format normalization

Prove what you changed

Every fix is a line you approved, exported as its own CSV. When a number is questioned, you have the answer.

Audit log export

03How it works

Four steps, and you make the decision in the third one

Drop the file

A CSV or TSV export. It is read on your machine, not uploaded.

CSV and TSV, up to 5MB in the browser

It finds the problems

Column types, duplicates, formats, encoding damage, missing zeros.

Nothing is changed at this point

03The step that matters

You approve each change

Every proposal shows the original value, the new value and the rule that fired. Approve it, reject it, or approve the lot. Nothing is written to your data behind your back, and your original file is never modified.

See the whole process

Download the clean file and the audit log

Two files: the cleaned CSV with only the changes you approved, and the change log listing every proposal and what you decided.

04The demo, running for real

Run it on your own file, right here

This is the product, not a video of it. Load one of the messy samples or drop your own CSV. Everything below is computed in your browser.

1. Load a file

Drop a CSV here or tap to browse. CSV and TSV, up to 5MB.

Your file is read on your own machine. Nothing is uploaded, so nothing can leak.

Or start from a messy sample

Status

Loading the sample file.

File: CRM contact export

Rows

Columns

Changes

Duplicate rows

Date formats

Blank or invalid emails

Load a file to see the diff

Drop a CSV or pick one of the messy samples. Every proposed change appears here as a line you approve or reject.

2. Review every change

Nothing approved yet.

Nothing is applied to your file until you approve it, and your original file is never modified.

Proposed changes

Original Proposed

05Before and after

Five rows from the sample order list

A different file from the one in the sheet at the top of this page, so these are five rules you have not already watched fire. Original on the left, proposal on the right.

Column	Original	Proposed	Rule
Customer Name	Marie-Claire DuprÃ©	Marie-Claire Dupré	Encoding repair
Order Date	46205	2026-07-02	Date format
Order Total	(45.00)	-45.00	Currency format
Ship Zip	7302	07302	Leading zero
Country	U.S.A.	United States	Country standard

46205 is what a spreadsheet leaves behind when a date column is stored as a serial number. The same file also holds four duplicate clusters, proposed separately, with the more complete row kept.

06For the person who signs off

What dirty records cost before anyone files a ticket

The spend is easy to see once you look for it, and none of it appears as a line item.

Enterprise plan

Spend against duplicates

Every duplicate contact is a second send, a second touch and a second entry in the pipeline. The budget is real and it is spent twice.

Forecasts built on doubles

Two records for one account inflate coverage and split the activity history. The forecast is wrong in a direction nobody checks.

Analyst hours, every quarter

The cleaning gets done by hand by the person who can least afford the afternoon, and none of that work is reusable next time.

The number nobody can defend

When a total is challenged, an audit log of approved changes ends the argument in a minute. Without one it takes a week.

What the Enterprise plan adds

Several people on one invoice, a DPA on request, invoicing and PO, and a named support contact, from $49 a seat a month billed yearly. Details on the enterprise page and the security page.

07How it compares

Against the three things you would otherwise do

Category level facts you can check yourself. There are no scores and no stars here.

	Excel Remove Duplicates	Open-source desktop tool	Enterprise platform	DataUntangler
Matching	Exact values only	Clustering you configure	Fuzzy, configurable	Fuzzy, run for you
Review before change	No	Partly	Varies	Every row
Record of what changed	A row count	In-project history	Yes	CSV audit log
Install needed	Spreadsheet app	Desktop install	Deployment project	None
Time to first result	Minutes	An afternoon	Weeks	Under a minute

Longer comparisons, one per tool, with where each one wins: vs OpenRefine, vs Cloudingo, vs Insycle, vs WinPure, vs Alteryx, vs KNIME, vs Dedupely and vs Data Ladder.

08 By system

Duplicate cleanup for the system your file comes from

Each page below covers one export: how that system matches duplicates, where it stops, and the reviewed list you approve before you import or merge.

CRM records

Email marketing lists

Accounting and ERP

Any CSV or Excel file

Comparing tools before you buy

Two plans, every file you have

Yearly billing saves 50 percent. The browser demo is one file of your own, no card required.

Yearly billing saves 50 percent, half the monthly price.

Switch to yearly and save 50 percent.

Analyst

Self-serve

One person with files to clean, as many as they like.

$29$59/mo

Billed $348 a year Billed monthly

Buy Analyst, yearly Buy Analyst, monthly

Unlimited files
Files up to 25MB, about 100,000 rows
Exact and fuzzy duplicate detection
Dates, numbers, currencies, encoding and casing fixed
Every change reviewable before you download
Cleaned CSV and a change log, both downloadable
Runs in your browser: files never leave your machine
Email support

Enterprise

Several people on one invoice, a DPA on request, priced per seat.

$49$98/seat/mo

Billed $588 a seat a year, from 2 seats ($1,176) Billed monthly per seat, from 2 seats ($196)

Buy Enterprise, yearly Buy Enterprise, monthly

Everything in Analyst
Several people on one invoice
DPA on request
Invoicing and purchase orders
A named contact for support

Payment is by card through our payment provider, monthly or yearly, and you can cancel from your account at any time. The free try is one file of your own, up to 5MB, in the browser demo. Already paid? Sign in.

Questions people ask before they trust a cleaning tool

Does my file get uploaded anywhere?

No. The demo runs entirely in your browser using JavaScript on your own machine. Your file is never sent to us, never stored and never seen by anyone. You can check it yourself: open your network tab, load a file, and watch that no request goes out.

Will it change something I did not want changed?

No. Nothing is applied until you approve it. Every proposed change is one line showing the original value, the new value and the rule that fired, and you approve or reject it row by row or in bulk. Your original file is never modified: you download a new file.

How is this different from Remove Duplicates in Excel?

Excel matches exact values only, so Acme Corp and Acme Corp. both survive, and Jose in one row and JOSE in another are treated as two different people. It also deletes rows without telling you which ones went. DataUntangler matches fuzzily across name, company and email, and shows you every row before anything happens.

How big a file can it handle?

The free try reads CSV and TSV files up to 5MB or 20,000 rows. The Analyst plan raises that to 25MB and 100,000 rows. On both, the file is read on your own machine rather than on a server.

Do you sell or train on my data?

No. We do not sell data, we do not share it with advertisers, and we do not use customer files to train any model. The browser demo never receives your file in the first place. What we handle on paid plans is described in plain language on the security page.

What happens after I sign up?

You enter your email, we send you a six digit confirmation code, and once you enter it your address is confirmed. The confirmation screen then tells you exactly what happens next. There is no card required to use the browser demo, and the demo is not a trial with a countdown on it.

Clean the file, and be able to show what you changed

Try the demo on your own CSV first. It runs in your browser, it costs nothing, and no card is required.

No card required. Your file never leaves your computer.