All 100 tools
Grouped by the kind of data they work on. Every one runs entirely in your browser and publishes the full list of checks it makes.
Every tool is a separate checker with its own rule set — the pages share a layout and nothing
else. Rule identifiers such as GTIN-005 or GMC-Q03 are stable, so a
finding can be cited in a ticket or a supplier spec and looked up here later. Each tool page
also lists the tools most often needed alongside it, with a line on why.
E-commerce product data
Product identifiers 19
Barcodes and the other numbers that name a product.
- GTIN / UPC / EAN ValidatorValidate barcodes in bulk: check digits, GS1 prefixes, Excel corruption, restricted ranges and placeholder codes.
- GTIN Check Digit CalculatorComplete a UPC, EAN or GTIN-14 from its first digits — with the step-by-step Mod-10 calculation shown.
- GTIN Format ConverterConvert barcodes between UPC-A, EAN-13 and GTIN-14 case codes in bulk — validated first, check digits recalculated, CSV out.
- GS1-128 ParserDecode the string under a logistics barcode into its Application Identifiers — with the FNC1 separator rule that most parsers get wrong.
- GS1 Element String BuilderBuild a GS1-128 element string from AIs: separators in the right places, check digits verified, output parsed back to prove it reads.
- GS1 DataMatrix GeneratorGenerate a GS1 DataMatrix from AIs: FNC1 in first position, symbol size in modules and millimetres, quiet zone stated.
- GS1 Digital Link CheckerCheck a Digital Link URI against the current standard — qualifier order, the new 14-digit GTIN rule, removed alphabetic names — and get the corrected URI back.
- Digital Link QR GeneratorGenerate a Sunrise-2027-ready GS1 Digital Link QR code — GTIN validated first, qualifiers in the mandated order, print-size guidance included. No valid data, no code.
- VIN Check Digit ValidatorVerify a VIN check digit, decode its sections, and see every model year the year code could mean — the ambiguity most decoders hide.
- IMEI ValidatorCheck an IMEI Luhn digit, complete a 14-digit one, and tell IMEI apart from IMEISV — the 16-digit form no checksum can validate.
- Container Number ValidatorValidate a shipping container number against ISO 6346 — including the letter values that skip multiples of 11, where hand-written code always goes wrong.
- Barcode GeneratorGenerate print-ready EAN-13, UPC-A, EAN-8 and ITF-14 barcodes as SVG — with the check digit validated before anything is drawn.
- UPC-E ⇄ UPC-A ConverterExpand the short 8-digit barcode on small packages to its full UPC-A — with the zero-suppression rule shown, and EAN-8 told apart from UPC-E.
- ISBN Converter & ValidatorConvert ISBN-10 ⇄ ISBN-13 with both forms shown at once — correct mod-11 check character, and an honest answer for 979 ISBNs.
- GS1 Key Validator (SSCC, GLN, GRAI…)Validate any GS1 key: SSCC, GLN, GRAI, GIAI, GSRN, GDTI, GINC, GSIN, GCN, and the GMN check character pair used as the EU Basic UDI-DI.
- ISSN & ISRC ValidatorCheck journal ISSNs (which have a check digit) and recording ISRCs (which have none), and convert between an ISSN and its 977 barcode.
- CAS & NDC Code CheckerVerify CAS Registry check digits and convert NDC drug codes to the 11-digit billing form — showing all three readings when the hyphens are missing.
- ITF-14 Case Code CheckerCheck an ITF-14 carton barcode against the GS1 General Specifications — X-dimension, bar height, quiet zones and bearer bars — and get its printed size before it goes on the carton.
- Variable Measure Barcode DecoderDecode a price- or weight-embedded in-store barcode (02, 20–29): item reference, the embedded price or weight under each documented national scheme, and the GS1 price check digit — or build one.
Listing content 5
The text a buyer reads, and the limits each marketplace puts on it.
- Description HTML CheckerSee which parts of a product description HTML the marketplace will silently remove — and which unclosed tag is breaking the page around it.
- Slug & Handle GeneratorTurn titles into URL slugs and Shopify handles — showing both romanisations where a name has two, and what the platform silently creates when handles collide.
- Amazon Search Terms Byte CounterCount backend keywords in bytes (not characters), see which words cost the most, and catch the waste that silently kills indexing.
- Product Title CheckerCheck a title against every marketplace's length limits and style rules, with the problems highlighted on the words themselves.
- Bullet Point Linter & Claim ScreenerCheck listing bullets for length, caps, HTML and off-platform contact details, and screen the copy for FDA/FTC claim language — with the reason each phrase is risky.
Images & media 6
What a platform will reject about a file before anyone sees it.
- Colour Space CheckerFind out whether an image is secretly CMYK — the one defect that looks completely normal until the marketplace rejects it.
- EXIF Privacy CheckerSee whether a product photo carries GPS coordinates, your name or a camera serial number — and strip them without re-encoding the image.
- Amazon Main Image CheckerSee the actual RGB of your image's background — the difference between 250 and 255 that your eye cannot catch but Amazon's scanner does.
- Media Spec AuditorAudit a whole batch of images and videos against every marketplace’s size, file size and format limits — as a matrix.
- Image Converter & ResizerConvert and resize product images to marketplace presets — Amazon, Google Shopping, eBay — then recheck them against the platform rules, locally.
- Bulk Image CompressorCompress PNG and JPEG in bulk without uploading anything — smart quantization or true lossless, with the loss measured and shown per file.
Prices & numbers 2
Values that mean different things depending on who reads them.
- Feed Unit ConverterConvert dimensions and weights in bulk and see what rounding to the field precision actually costs — the factors are exact, the rounding is not.
- Price & Number Format CheckerCatch the ambiguous decimal separator that turns 19,99 into 1999 — plus ISO 4217 currency codes and their decimal places.
Shipping & logistics 10
Getting the goods, and the paperwork, to move.
- Lithium Battery CheckerWork out watt hours correctly — the cell voltage, not the USB output — and see which passenger-carriage band a battery falls into.
- Air Waybill ValidatorCheck an 11-digit air waybill number against its modulo-7 check digit — and learn why none of them ever ends in 7, 8 or 9.
- Tracking Number Carrier IdentifierWork out which carrier a tracking number belongs to — and verify its check digit where the algorithm is public, instead of guessing from the shape.
- Dimensional Weight CalculatorCompare dimensional weight across carrier divisors, and get the break-even box size at which volume stops setting the price.
- UN Number LookupSearch the Hazardous Materials Table by product name or UN number, and see every entry sharing that number with its own limits.
- Incoterms CheckerCheck whether a trade term is valid for how the goods actually travel — FOB on a container is the classic contract error.
- HS Code CheckerCheck a tariff code against every published heading and subheading - and see what each pair of digits means, and who decides it.
- FNSKU Label GeneratorPrint Amazon FBA labels that scan: paste FNSKUs, get an exact-size PDF for 30-up sheets or thermal rolls — bars aligned to your printer’s dot grid, with a calibration page to catch "fit to page".
- GS1 Logistic Label GeneratorGenerate compliant SSCC pallet labels in your browser: three-block GS1 layout, 31.75 mm bars on the printer dot grid, exact-size PDF and ZPL from the same engine — every number cited to the GS1 General Specifications.
- ZPL ViewerRender Zebra ZPL II in your browser — no upload, no print quota. Code 128 drawn with a verified encoder, unsupported commands listed by name, exact-size PDF export.
Feeds & files 11
Whole files — before you upload them, and after a spreadsheet has been at them.
- Google Shopping Feed ValidatorCatch Merchant Center disapprovals before you upload: required attributes, GTIN validity, identifier logic, price and enum formats.
- Shopify Product CSV ValidatorCheck a product CSV before importing — including the handle collisions that silently overwrite live products.
- WooCommerce Product CSV ValidatorForecast a WooCommerce import before you run it: which rows create, which are silently skipped, and which columns never get mapped.
- Shopify ⇄ WooCommerce CSV MigratorConvert a product export between Shopify and WooCommerce — variants restructured, sale prices un-swapped, unmapped columns listed.
- CSV Dialect DetectorFind out which CSV dialect a file actually is — delimiter, quoting, line endings, BOM — detected by column consistency, not by counting commas.
- CSV ⇄ Excel Safe ConverterConvert CSV to .xlsx without Excel eating your barcodes — identifier columns are auto-protected as text — and convert workbooks back to clean CSV with every change disclosed.
- Excel Damage DiagnosticFind out what a spreadsheet broke in your column — and whether each value can still be repaired or is gone for good.
- Product Feed DiffCompare two feed exports aligned by SKU rather than by line — so reordered rows produce no false differences.
- Marketplace Feed ValidatorCheck a product feed for Meta, TikTok, Walmart or Amazon — and catch the values that are correct on the platform you copied it from.
- Google ⇄ Meta Feed ConverterConvert a Google Shopping feed to a Meta catalog feed - translating the values that differ and leaving blank the two that have no equivalent.
- Feed RepairerRepair a damaged feed in one pass - mojibake, spreadsheet damage, invisible characters - and get a list of every cell it would not guess at.
Compliance wording 8
Statements where the law fixes the words and “close” loses the safe harbour.
- Compliance Statement CheckerCheck Prop 65 warnings against the safe-harbour wording, allergen declarations against the nine major US allergens, and CE / UKCA / FCC claims for a verifiable reference.
- Nutrition Facts Rounding CheckerTurn lab values into the numbers a US Nutrition Facts panel must print — per-nutrient increments, %DV, and the consistency checks.
- Fragrance Allergen Threshold CheckerConvert a supplier certificate into concentrations in the finished product and see which allergens must be named in the EU ingredient list.
- CPSC Certificate Checker (CPC / GCC)Check a Children’s Product Certificate or GCC against 16 CFR 1110 — every required party, the identifier’s check digit, and the prescribed attestation.
- EU Declaration of Conformity CheckerPaste a supplier’s EU Declaration of Conformity and see which items the applicable annex actually requires — RED, EMC, LVD, Toy Safety, RoHS, PPE and Machinery each ask for a different list.
- EU Nutrition Declaration CheckerCheck an EU nutrition declaration: Annex XIV energy, the rounding tier each value must sit on, and the range an official control accepts.
- GPSR Listing Compliance CheckerCheck a listing against Article 19 GPSR: manufacturer contact, EU responsible person, product identification and warnings per market language.
- Textile Label CheckerCheck fibre content against 16 CFR 303 — including the under-5% "other fiber" rule — and care wording against 16 CFR 423.
Storefront & SEO 5
Markup that fails silently — the page looks fine and the machine sees nothing.
- Product JSON-LD CheckerValidate Product structured data without publishing the page — including the barcode, the currency and the comma that turns 19,99 into nothing.
- UTM CheckerCompare a whole set of campaign URLs and find the values that differ only by case — the split that every single-URL checker misses.
- hreflang CheckerValidate hreflang annotations and get back the identical block every page in the set must carry — starting with why en-UK does nothing.
- Open Graph CheckerSee the share card your meta tags produce, and catch the two failures a browser never shows: name= instead of property=, and relative image URLs.
- Email Merge Field CheckerRender an email template with a full record and with the fields empty, and catch unclosed merge fields or two syntaxes pasted into one template.
Selling across borders 5
Formats that change at every border you cross.
- Postcode Format CheckerCheck a postcode column against each country’s usual format — separating a spacing problem from one that needs a real lookup.
- Country Code CheckerCheck and convert ISO 3166-1 country codes — and find the ones that look right but are not assigned, starting with UK.
- IBAN & SWIFT/BIC ValidatorCheck IBAN check digits and per-country layout, and SWIFT/BIC structure — including test BICs, which look completely normal until a payment fails.
- EU VAT & EORI CheckerCheck EU VAT numbers and EORI numbers against their published formats — including the GR-for-EL and GB-for-XI prefix traps.
- Shoe Size ConverterConvert EU, UK and US shoe sizes from the unit definitions with the working shown — and see why apparel size charts are not trustworthy.
Data hygiene 5
Characters and values that are not what they look like.
- Mojibake FixerRepair text mangled by an encoding mix-up — by working out the actual encoding chain, not by matching a substitution table.
- Mixed Script DetectorFind full-width punctuation and lookalike letters from another script — the characters that survive proofreading because they look right.
- Date Format CheckerShow every reading of an ambiguous date, decode spreadsheet serial numbers, and check Merchant Center date ranges and time zones.
- Invisible Character DetectorFind the zero-width spaces, BOM and look-alike characters hiding in your text — and see what each one is doing to your data.
- Duplicate & Variant Value AuditorFind which values in a column are the same thing — exact duplicates, spelling differences, and synonym sets like L and Large.
Business documents & regulated formats
Compliance wording 1
Statements where the law fixes the words and “close” loses the safe harbour.
E-invoicing 8
Documents that get rejected for their shape before anyone reads the amount.
- Commercial & VAT Invoice GeneratorGenerate a commercial, VAT or proforma invoice with every mandatory particular checked as you type — then print to PDF, all in your browser.
- Invoice Fields CheckerCheck an invoice against the particulars EU VAT law requires, and whether net, VAT and total agree — with the EN 16931 rule numbers.
- EN 16931 Code ListsSearch the invoice type, VAT category, payment means and allowance reason codes — and see which official rules a VAT category brings into force.
- Peppol Invoice CheckerCheck a UBL invoice against the published Peppol BIS Billing 3.0 rules - reported under their official identifiers so every finding can be looked up.
- Origin Declaration CheckerCompare the preferential origin declaration on your invoice against the wording EU law prescribes - word for word, in every prescribed language.
- Supplier's Declaration CheckerPick the right one of the four prescribed supplier's declarations, and check a long-term validity period against the limit the annex actually states.
- E-Invoice IdentifierTell UBL from CII, read the CustomizationID, and find out which profile an e-invoice declares - Peppol, XRechnung or the EN 16931 core - before you validate it.
- XRechnung CheckerCheck a German XRechnung invoice against KoSIT's official BR-DE rules, in UBL or CII, reported under their official identifiers.
PDF & files 12
The documents themselves: diagnose, merge and split PDFs without uploading them.
- PDF MergerMerge PDFs in your browser — nothing is uploaded. Every file is structure-checked first (truncation, encryption, missing header), bad files are skipped with a diagnosis, and the output is verified with an independent parser.
- PDF SplitterSplit a PDF or extract pages in your browser — nothing is uploaded. Page ranges like 1-3,5,9- with real error messages, structure diagnosis before anything runs, one file or one-per-page.
- PDF CompressorShrink scanned and image-heavy PDFs in your browser — no upload, no size cap. Every image reports its before/after size, resolution and PSNR, and a file that cannot be improved comes back untouched instead of re-saved.
- PDF Page OrganizerReorder, rotate and delete PDF pages by looking at them — thumbnails render in your browser, nothing is uploaded. Rotation is relative, so pages that were already rotated do not end up sideways.
- PDF UnlockerRemove a PDF password in your browser with the password you already have — the document and the password never leave your machine, and nothing is cracked or bypassed.
- PDF OCR (Searchable Scans)Add an invisible, searchable text layer to a scanned PDF — OCR runs as WebAssembly in your browser, and the scan itself is never touched.
- PDF Form Filler & CheckerFill a PDF form and see what would get it rejected — empty required fields, values outside the options, fields that secretly share a name.
- Images to PDFTurn JPEG and PNG files into a PDF with the layout decisions shown — what gets enlarged, what gets cropped, what resolution it prints at.
- PDF Text ExtractorPull the text out of a PDF — and see which pages have no text layer at all instead of getting an empty string back.
- PDF Attachments & Factur-X CheckList the files embedded in a PDF, check a Factur-X / ZUGFeRD container, and run the invoice inside it against Article 226.
- PDF Redaction CheckerCheck whether a redacted PDF really removed the text or just covered it — recoverable text shown verbatim, plus metadata, history and annotation leaks.
- PDF Hidden Content FinderSee what a recipient can still recover from a PDF — text hidden outside the crop box shown verbatim, plus layers that are off by default, document properties and save history.
Bookkeeping & audit trail 1
The sequences and references a tax authority expects to be unbroken.
Company identifiers 1
Codes that say which legal entity you are — and what a well-formed wrong one costs.
Payment references 1
The structured codes that let an incoming payment reconcile itself against the right invoice.