I will clean, deduplicate and standardize your messy dataset in Excel or Python

I will clean, deduplicate and standardize your messy dataset in Excel or Python

About this gig

I will clean, deduplicate, and standardize your messy dataset in Excel or Python so it's analysis-ready, consistent, and free of the errors that quietly break reports and dashboards.

If your spreadsheet is full of duplicate rows, inconsistent date formats, stray whitespace, mismatched categories, and half-empty columns, I will turn it into a clean, structured, reliable file you can actually trust.

What you get

I focus on one thing and do it well: taking a messy dataset and making it clean, consistent, and ready for whatever comes next: reporting, import into a CRM, machine learning, or a board deck. Concrete deliverables include:

  • A cleaned dataset delivered in your preferred format (XLSX, CSV, Google Sheets, or a database-ready file), with the original left untouched so you always have a fallback.
  • Deduplication using exact and fuzzy matching. I catch the obvious duplicates and the sneaky ones too: "Acme Inc." vs "Acme, Inc." vs "ACME INCORPORATED", or the same person entered twice with a typo in the email.
  • Standardized formatting across the board: consistent date formats (e.g. YYYY-MM-DD), normalized phone numbers, trimmed whitespace, unified casing for names and categories, and consistent units or currency notation.
  • Missing-value handling done transparently. I flag blanks, fill where a rule clearly applies, and never silently invent data. You decide whether gaps are left empty, filled with a default, or marked for review.
  • Type correction so numbers stop being stored as text, dates stop being read as strings, and your sort and SUM functions finally behave.
  • Validation and outlier flags: invalid emails, impossible dates, negative quantities, out-of-range values, and other red flags surfaced in a separate column or sheet rather than dropped without notice.
  • A short change log listing what I cleaned, how many duplicates were removed, which columns were standardized, and any decisions I made along the way. No black box.
  • The cleaning script (Python/pandas) on request, so you can re-run the same process on future exports yourself.

Plans

FeatureBasicStandardPremium
Rows coveredUp to ~2,000Up to ~20,000Up to ~100,000+
ColumnsUp to 10Up to 25Unlimited
Remove duplicates (exact)YesYesYes
Fuzzy/near-duplicate matchingYesYes
Standardize dates, text, casingYesYesYes
Phone/email/format normalizationBasicYesYes
Missing-value handlingFlag onlyFlag + rule-based fillCustom rules
Validation & outlier reportYesYes
Multiple files / merge & join1 mergeMultiple
Reusable cleaning script (Python)Yes
Change log / documentationBriefDetailedDetailed + walkthrough
Revisions12Unlimited (within scope)

Row and column counts are guides, not hard walls. Send me a sample and I'll tell you exactly which tier fits before you commit.

How it works

  1. You send the data and the goal. Share the file (or a representative sample if it's sensitive) and tell me what you need it for. "Import into HubSpot," "feed a Power BI dashboard," and "train a model" all imply different cleaning choices.
  2. I audit it and reply with a plan. Within the first review I tell you what's wrong: duplicate count, format inconsistencies, missing-data hotspots, and any structural issues. You approve the approach and confirm the edge-case rules.
  3. I clean it. Working on a copy, I deduplicate, standardize, correct types, handle blanks per your rules, and flag anything that needs a human decision.
  4. I validate. I cross-check totals, row counts, and key fields so the cleaned file reconciles against the original. Nothing should silently disappear.
  5. You review and I revise. You get the cleaned file plus the change log. If a rule needs adjusting, I refine it within your plan's revisions.

Why choose this

  • Honest, transparent process. I never delete or alter data without a documented rule. Every change is logged so you can audit exactly what happened.
  • The right tool for the size. Small, one-off files get handled cleanly in Excel/Sheets. Large or recurring jobs get a Python/pandas pipeline that's fast, repeatable, and reusable.
  • Fuzzy matching that actually works. Exact-match dedup is easy; the value is in catching the near-duplicates that inflate your counts and skew your reports.
  • Built for what's next. I clean with the destination in mind, so the output drops straight into your CRM, BI tool, or model without another round of fixes.
  • No invented data. Where information is genuinely missing, I flag it rather than guess. You stay in control of every judgment call.

Who it's for / use cases

  • Marketers and sales teams consolidating lead lists, removing duplicate contacts, and standardizing before a CRM import or email campaign.
  • Analysts and operations preparing exports for dashboards in Power BI, Tableau, Looker, or plain Excel pivot tables.
  • E-commerce and inventory owners unifying product catalogs, SKUs, prices, and supplier feeds from multiple sources.
  • Researchers and students cleaning survey responses or scraped data before analysis in Excel, R, or Python.
  • Data scientists who need a clean, consistent training set without spending days on tedious preprocessing.
  • Finance and admin teams reconciling records from several systems where the same entity appears in several inconsistent forms.

FAQ

Q: What file formats do you accept and deliver? I work with Excel (XLSX/XLS), CSV, TSV, Google Sheets, and JSON. I can also deliver a database-ready file or load directly into a Google Sheet. Tell me your preferred output and I'll match it.

Q: Will you change my original data? No. I always work on a copy and return the cleaned version separately, so your source file stays intact as a reference and fallback.

Q: How do you handle duplicates that aren't exactly identical? On Standard and Premium I use fuzzy matching to catch near-duplicates: slight spelling differences, extra punctuation, swapped name order, or typos in emails. Before merging anything ambiguous, I confirm the matching rules with you.

Q: What about missing values? Will you make up data? Never. I flag blanks clearly. Where a safe rule applies (for example, a default region or a zero quantity you've confirmed), I fill per your instruction. Anything uncertain is marked for your review rather than guessed.

Q: My data is confidential. Can we work around that? Yes. You can send a representative sample or anonymized/masked version so I can build and prove the cleaning process, then you run the finished script on the full file yourself. I'm happy to keep sensitive fields out of scope entirely.

Q: Do I get the script, or just the cleaned file? Basic and Standard deliver the cleaned file and a change log. Premium includes the documented Python/pandas script so you can re-run the exact same cleaning on future exports without re-ordering.

Q: How long does it take? Small files are usually quick; larger or multi-file jobs with merges and custom rules take longer. After I see a sample I'll give you a realistic timeline up front, before any work begins.

Q: What if the result isn't quite right? Each plan includes revisions. If an edge case slipped through or a rule needs tuning, send it back and I'll adjust within your plan's scope. My goal is a file you can use immediately, with no surprises.

Reviews4.8(4)

  • @kaidev
    ★★★★★5

    My nonprofit's donor spreadsheet had names in every format imaginable and a ton of near-duplicates. They caught fuzzy matches I never would have spotted manually and standardized all the phone numbers and zip codes. Communication was quick and clear the whole way through.

  • @mintmind
    ★★★★★5

    Sent over a 40k-row customer list from our e-commerce store that was riddled with duplicate emails and inconsistent state abbreviations. Got it back fully deduped and standardized in under two days, and the Python script was even included so I can rerun it on next month's export. Honestly saved me a whole weekend.

  • @noracodes
    ★★★★4

    Good work cleaning up a messy real estate listings dataset. A couple of address fields needed a second pass after I clarified the format I wanted, but they fixed it same day without any fuss.

  • @sophia7
    ★★★★★5

    Turned a chaotic Excel file of survey responses into something I could actually pivot on. Trailing spaces gone, categories normalized, duplicates removed. Fast turnaround and very responsive.