SEO
Schema markup generator
Build FAQ, HowTo, Article, Product, LocalBusiness, Breadcrumb, and Organization JSON-LD.
No upload. No account.
A utility shed that stays on your device.
Plaintools runs every converter and generator in the browser. Files, tokens, IBANs, and campaign URLs never leave the tab. Use it when you do not want another paste-bin with a login.
Live tools
SEO
UTM generator
Add source, medium, campaign, term, and content parameters to a URL you already own.
SEO
Slug generator
Turn a title into a lowercase URL slug, with stop words stripped and unicode transliterated.
Dev
JWT decoder
Read a JWT header and payload, with human timestamps and an expired flag. The token stays in the tab.
Dev
JSON to CSV converter
Turn an array of objects into a CSV, flattening one level of nested objects.
Dev
YAML to JSON converter
Convert YAML to JSON, or JSON to YAML, in one page. Parsing stays in the browser.
SEO
JSON-LD generator
Build live JSON-LD for FAQ, HowTo, Article, Product, LocalBusiness, Breadcrumb, and Organization.
Convert
HEIC converter
Convert iPhone HEIC/HEIF photos to JPEG or PNG in the browser.
Dev
Text diff checker
Compare two texts with a live line and word diff. Optional ignore-whitespace.
Checkers
IBAN validator
Check an IBAN checksum and country length. The number never leaves this tab.
Finance
Seller financing calculator
Estimate monthly payment, interest, and an optional balloon on a seller note.
Build
Deck material calculator
Estimate board count and linear feet from deck size, board width, gap, and waste.
Dev
Hash generator
Calculate SHA-256, SHA-384, SHA-512, and SHA-1 checksums for text or local files.
Dev
Timestamp converter
Convert Unix epoch timestamps in seconds or milliseconds to ISO 8601, UTC, and local time.
Dev
CSV to JSON converter
Convert CSV records to a JSON array of objects with header mapping and type detection.
Finance
Owner financing calculator
Calculate monthly payments, total interest, and balloon payoff from the buyer's perspective.
Finance
Pool financing calculator
Calculate swimming pool loan monthly payments, interest, down payment, and amortization schedule.
Finance
XIRR calculator
Calculate annualized internal rate of return for irregular, dated investments and cash flows.
Build
Roof pitch calculator
Calculate roof pitch (x/12), slope angle in degrees, grade percentage, and common rafter length.
SEO
Open Graph generator
Generate Open Graph and Twitter Card meta tags with live social preview cards.
Dev
Subnet calculator
Calculate IPv4 network address, broadcast, usable range, subnet mask, and host capacity from CIDR.
SEO
Favicon generator
Generate multi-resolution favicon.ico, 16/32/48 PNGs, apple-touch-icon, and web manifest locally.
SEO
Robots.txt generator
Generate RFC 9309 robots.txt files with allow/disallow paths, bot groups, sitemaps, and crawl delays.
Shipping
Etsy fee calculator
Estimate Etsy listing fees, 6.5% transaction charges, payment processing, and net profit margins.
Dev
CIDR calculator
Calculate IPv4 CIDR blocks, network address, broadcast address, netmask, usable hosts, and wildcard mask.
SEO
Schema checker
Validate Schema.org JSON-LD syntax, @context, @type, and required fields for FAQ, HowTo, Article, and Product.
Convert
Image compressor
Compress JPEG, PNG, and WebP images with adjustable quality, scaling, and live file size preview.
Finance
Break-even calculator
Calculate break-even units, revenue, contribution margin, and target profit volume milestones.
Convert
GIF compressor
Compress animated and static GIFs in your browser by downscaling dimensions, quantizing colors, and dropping frames.
Text
Case converter
Convert text between lowercase, UPPERCASE, Title Case, Sentence case, camelCase, PascalCase, snake_case, and kebab-case.
Text
Readability checker
Calculate Flesch Reading Ease, Flesch-Kincaid Grade Level, Gunning Fog, and reading time estimates client-side.
Finance
Retirement corpus calculator
Calculate the required retirement corpus, future monthly living expenses adjusted for inflation, and required monthly savings.
Convert
PDF to JPG converter
Convert PDF pages into high-resolution JPG images client-side. Download single pages or a multi-page ZIP.
Convert
Video compressor
Compress and shrink MP4, MOV, and WebM videos client-side using WebAssembly. Files never leave your device.
Finance
GST calculator
Calculate Indian Goods and Services Tax (GST), CGST, SGST, IGST, and net/gross invoice values client-side.
SEO
Hreflang generator
Generate HTML link tags, XML sitemap snippets, and HTTP headers for multilingual and multi-regional hreflang SEO.
Coming next
AVIF converter
Same privacy model as HEIC: decode in the tab, download a JPG or PNG. Not shipped yet.
robots.txt checker
Paste a robots file and a path; see which rules match. Parsing only, no crawl.
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