Online tools
A list of free online tools: JSON, PDF, SQL, hashes, regex, SEO, and other development tasks, in the browser.
Data
- JSON formatterTurn JSON into readable indentation, or keep it compact.
- JSON validatorCheck that text is valid JSON and see the root value type.
- JSON to YAMLConvert valid JSON into YAML.
- YAML to JSONConvert YAML into formatted JSON.
- JSON minifierCompress valid JSON onto one line.
- JSON diffCompare two JSON values by structure, with keys sorted.
- JSON to CSVConvert a list of JSON objects into CSV.
- CSV to JSONConvert a headed CSV into a JSON list.
- JSON to XMLWrap JSON in XML elements.
- XML to JSONConvert well-formed XML into JSON.
- XML formatterIndent well-formed XML.
- XML validatorCheck that XML is well-formed.
- YAML formatterRewrite YAML with stable indentation.
- YAML validatorCheck that YAML can be parsed.
- TOML formatterRewrite valid TOML.
- TOML validatorCheck TOML syntax.
- JSON Schema validatorCheck JSON data against a JSON Schema.
- JSON Schema generatorInfer a simple schema from an example.
- JSONPath testerQuery JSON with a path that starts at $.
- Flatten JSONTurn nested objects into dotted keys.
Encoding
- Base64Encode and decode Base64 text, including accented characters.
- URL encoderEncode or decode a URL component.
- Base64URL converterShow standard Base64 and URL-safe Base64.
- HTML entity encoderReplace & < > and quotes with entities.
- HTML entity decoderTurn named and numeric entities into characters.
- Unicode inspectorShow the code point and UTF-8 bytes of each character.
- UTF-8 byte counterCount characters, UTF-16 units, and UTF-8 bytes.
- Hex to textConvert hexadecimal bytes into UTF-8 text.
- Text to hexShow UTF-8 bytes in hexadecimal.
- Binary to textConvert groups of 8 bits into UTF-8 text.
- Text to binaryShow each UTF-8 byte as 8 bits.
- ROT13Rotate Latin letters by 13 places.
- SHA-256 generatorCompute the SHA-256 of a text.
- SHA-512 generatorCompute the SHA-512 of a text.
- HMAC generatorCompute HMAC-SHA256 with a key you provide.
- Hash verifierCompare two hashes without stopping at the first difference.
- SRI hash generatorBuild a sha384 integrity value for text content.
- File checksumCompute SHA-256 and SHA-512 for a file or a text.
Generators
- UUID generatorGenerate version 4 UUIDs with the browser's generator.
- Password generatorCreate passwords with the browser's cryptographic generator.
- QR code generatorCreate a PNG QR code from text or a link.
- Cron generatorBuild a five-field cron expression and read what it means.
- ULID generatorGenerate ULID identifiers with time and cryptographic randomness.
- Nano ID generatorGenerate 21-character IDs with the cryptographic generator.
- Passphrase generatorJoin words from a fixed list using cryptographic randomness.
- Lorem ipsumGenerate paragraphs of placeholder text.
- Fake dataGenerate example names, emails, and cities.
- JSON mockBuild JSON from uuid, name, email, int, and bool fields.
- INSERT generatorBuild INSERT statements from CSV or JSON.
- INSERT to UPDATEConvert a simple INSERT into an UPDATE using the first column in WHERE.
- HTML boilerplateGenerate a minimal HTML5 document.
- CSS resetGenerate a short original reset for a new page.
- .gitignore generatorBuild rules for node, python, go, java, and editors.
- Compose generatorBuild a service with an image and a port.
- Dockerfile generatorCreate a template for node, python, or static.
- Nginx generatorGenerate a server block with proxy_pass.
- Test workflowGenerate a workflow that installs Node and runs a command.
- Kubernetes manifestGenerate a simple Deployment and Service.
Validators
- Regex testerTest a JavaScript regular expression against text.
- JWT decoderRead the header and payload of a JSON Web Token.
- Email validatorCheck an email's shape without contacting the mailbox.
- URL validatorCheck that the text is an absolute URL.
- IPv4 validatorCheck four decimal octets without a leading zero.
- IPv6 validatorCheck the general form of an IPv6 address.
- UUID validatorCheck the format and report the version.
- Regex libraryLook up starter patterns for common tasks.
- HTML validatorCheck that opened tags are also closed.
- CSS validatorCheck that braces are balanced.
- JavaScript syntaxParse syntax without running the code.
- SQL syntaxCheck that the SQL formatter can read the statement.
- SemVer validatorCheck a semantic version.
- OpenAPI validatorCheck required fields of an OpenAPI or Swagger document.
- XML and XSDCheck that XML is well-formed and that the root appears in the pasted XSD.
- YAML schemaValidate YAML against a JSON Schema.
- MIME typesLook up MIME types for common extensions.
- Phone formatterGroup digits. Ten or eleven digits use the Brazilian shape.
- Card validatorCheck digit count, the brand prefix, and the Luhn checksum.
- IBAN validatorCheck the shape and the mod-97 checksum.
- Color contrastCalculate the WCAG ratio between two colors.
Time
- Timestamp converterConvert a Unix timestamp to a date and a date to a timestamp.
- Timezone converterShow an instant in UTC and in another zone.
- ISO 8601 formatterShow an instant as ISO, a date, and an ISO week.
- Date differenceCalculate days, hours, and the calendar difference.
- Age calculatorCalculate years, months, and days until today.
- Duration converterConvert durations with ms, s, m, h, and d.
- Epoch inspectorShow seconds, milliseconds, and ISO for a timestamp.
- Cron next runsList five future times for a five-field expression.
- Percentage calculatorCalculate p% of n, a/b, and n + p% or n - p%.
- Number base converterConvert an integer between bases 2 and 36.
- Binary calculatorAdd, subtract, multiply, and apply bitwise operations.
- Scientific notationShow a number in decimal and scientific notation.
- Random numbersGenerate integers with the browser's cryptographic generator.
- Basic statisticsCalculate sum, mean, median, min, max, and deviation.
- Byte converterConvert bytes between SI and IEC units.
- Transfer calculatorEstimate how long a size takes at a given rate.
- Subnet calculatorCalculate network, mask, broadcast, and range for an IPv4 CIDR.
- chmod permissionsConvert octal and symbolic rwx.
Text
- Text diffSee what changed between two texts, line by line.
- Word counterCount words, characters, and lines as you type.
- Character counterCount Unicode characters, UTF-16 units, and non-space characters.
- Line counterCount lines, blank lines, and non-blank lines.
- Reading timeEstimate reading time at 200 words per minute.
- Case converterShow upper case, lower case, title case, and sentence case.
- To camelCaseConvert separated words or other cases into camelCase.
- To snake_caseConvert a name to lowercase words and underscores.
- To kebab-caseConvert a name to lowercase words separated by hyphens.
- Duplicate line removerKeep the first occurrence of each line.
- Whitespace cleanerTrim edges, collapse inner spaces, and reduce blank lines.
- Line sorterSort lines with numeric comparison.
- Find and replaceReplace an exact text with another.
- Regex replaceReplace matches of a JavaScript expression.
- Text reverserReverse the order of Unicode characters.
- Slug generatorBuild a lowercase slug without accents.
- ASCII textDraw uppercase letters with a block font.
- Markdown tableConvert CSV into a Markdown table.
- Escape textEscape text as JSON string content, or unescape a quoted JSON string.
- CSV column extractorExtract a column by name or by 1-based position.
Formatters
- SQL formatterIndent a SQL query so it is easier to read.
- HTML formatterIndent HTML for reading.
- CSS formatterIndent CSS for reading.
- Markdown previewSee how Markdown renders, without executing raw HTML.
- HTML minifierRemove space and comments from HTML.
- CSS minifierCompress CSS rules.
- JavaScript formatterIndent JavaScript with Prettier.
- JavaScript minifierCompress JavaScript and shorten local names.
- TypeScript formatterIndent TypeScript with Prettier.
- JSONC formatterIndent JSON with comments and keep the comments.
- GraphQL formatterIndent a GraphQL operation.
- Markdown formatterNormalize Markdown with Prettier.
- Markdown to HTMLConvert Markdown to HTML and escape raw HTML.
- HTML to MarkdownConvert simple HTML into Markdown.
- SVG optimizerRemove comments, the XML prolog, and common editor metadata.
- XML minifierCompress well-formed XML.
- Python normalizerTurn tabs into spaces, trim line endings, and collapse blank lines.
- PHP formatterIndent braces in a PHP snippet.
- Shell formatterIndent then, do, and brace blocks.
- YAML minifierRewrite YAML in compact flow style.
Frontend
- PX to REMConvert pixels and rem using the base you choose.
- CSS gradientBuild a linear-gradient and show a preview.
- CSS shadowBuild a box-shadow.
- Border radiusGenerate border-radius in pixels.
- FlexboxBuild a flex container and show three boxes.
- CSS GridBuild equal columns and show a preview.
- CSS clampGenerate a fluid font-size with clamp.
- HEX to RGBConvert a hex color to RGB and HSL.
- RGB to HSLConvert rgb() or hex into HSL and back to hex.
- Color paletteGenerate five lightness variations.
- CSS animationGenerate a scale keyframe and the animation rule.
- CSS transformGenerate rotate and scale.
- Clip pathShow common clip-path shapes.
- SVG path viewerDraw a d attribute in a local SVG.
- SVG faviconGenerate an SVG favicon with one or two letters.
- BreakpointsList frequent media queries.
- HTML entitiesLook up frequent named entities.
- Data URIBuild a data URI from text or a small file.
- CSS specificityCalculate the (a, b, c) triple of a selector.
- Merge PDFJoin two or more PDFs in the chosen order.
- Split PDFGenerate one PDF per page.
- Rewrite PDFRewrite the PDF with object streams. It does not recompress images.
- PDF to imagesDraw the pages to PNG in this browser.
- Images to PDFCreate one page per PNG or JPEG.
- Rotate PDFRotate pages by 90, 180, or 270 degrees.
- Reorder pagesGenerate a PDF in the new order.
- Remove pagesDrop the listed pages.
- Extract pagesCreate a PDF with only the requested pages.
- Number pagesWrite the number in the footer of each page.
- WatermarkWrite diagonal text on each page.
- PDF metadataShow title, author, subject, and page count.
- Edit metadataSet title, author, and subject.
- Extract PDF textRead the text of each page and number the result.
- PDF to textJoin the text of the pages.
- PDF to MarkdownPlace each page's text under a heading.
- Fill a formFill text fields in a PDF.
- Page sizeShow each page in points and millimeters.
API
- Request builderBuild the HTTP message without sending it.
- cURL to fetchConvert a simple cURL command into fetch.
- cURL to PythonConvert a simple cURL command into requests.
- cURL to PHPConvert a simple cURL command into curl_setopt_array.
- HTTP codesLook up the meaning of frequent codes.
- Header inspectorList pasted headers and point out a few missing security headers.
- JWT signature verifierCheck HS256, HS384, HS512, or an RSA public key you paste.
- OAuth scopesLook up frequent OIDC, GitHub, and Google scopes.
- Webhook payloadShow an example JSON for GitHub, Stripe, or Slack.
- GraphQL builderBuild a query or mutation without sending it.
- GraphQL introspectionList types and fields from a pasted introspection JSON.
- OpenAPI to MarkdownList paths and methods from OpenAPI.
- HTTP response formatterIndent the JSON body of a pasted response.
- User-Agent parserPoint out browser and system from known tokens.
- URL parserSplit protocol, host, path, query, and hash.
- Query stringBuild an encoded query string.
- CORS headersGenerate the Allow headers of a response.
- WebSocket testerOpen a connection from this browser to the address you type.
- Webhook signatureCompute HMAC-SHA256 of the body with the secret you already have.
DevOps
- Compose validatorCheck that services exist and each has image or build.
- Dockerfile lintPoint out a missing tag, missing USER, ADD, and ENV names that look like secrets.
- docker run to ComposeConvert port, env, volume, and name into a service.
- Manifest validatorCheck apiVersion, kind, and metadata.name in each document.
- Kubernetes resourcesSum cpu and memory from requests and limits.
- Helm valuesGenerate a short values.yaml.
- .env comparatorShow keys on only one side and keys with different values.
- Redact .envReplace values with ***.
- Git commandsBuild status, clone, branch, commit, push, pull, or stash.
- Branch nameBuild type/ticket/description as a slug.
- Conventional commitBuild the first line and, if present, the breaking-change footer.
- SemVer comparatorSay which version is greater.
- ChangelogGroup conventional commits.
- GitHub workflowGenerate a CI or Pages workflow.
- Nginx validatorCheck braces, semicolons, and server_name.
- Apache rewriteGenerate Redirect and the equivalent Nginx rewrite.
- Linux chmodConvert the permission and show the chmod command.
- systemd serviceGenerate a simple unit file.
- Log timestampAppend the ISO form of numbers that look like epochs.
Database
- SQL minifierCollapse spaces and remove line comments.
- SELECT builderBuild a SELECT from fields.
- UPDATE generatorBuild an UPDATE and require WHERE.
- DELETE builderBuild a DELETE. Without WHERE it continues only when confirm is all.
- Table to JSONConvert a bar- or comma-separated table into JSON.
- JSON to SQLWrap JSON objects in INSERT statements inside a transaction.
- Text schemaDraw tables read from CREATE TABLE.
- ER diagramGenerate a Mermaid erDiagram from CREATE TABLE.
- SQL typesLook up frequent PostgreSQL types.
- Connection stringBuild a postgresql:// URL with the password encoded.
- MongoDB formatterIndent the object of a shell query.
- MongoDB to JSONReplace ObjectId, ISODate, and NumberLong with JSON.
- BSON inspectorRead the length and names of a BSON document in hexadecimal.
- Redis commandBuild a known command and explain the verb.
- Index suggestionSuggest an index from the WHERE columns.
- Database seedGenerate fictional INSERT statements.
- Migration templateGenerate a CREATE TABLE from name:type.
- Table namesShow snake, camel, pascal, and kebab.
SEO
- HTTP status explainerExplain a pasted code. It does not request the URL.
- Meta tagsGenerate title, description, and canonical.
- Meta analyzerRead title, description, canonical, and robots from pasted HTML.
- Open GraphGenerate the og meta properties.
- Twitter cardGenerate a summary_large_image card.
- robots.txtGenerate a robots.txt with allow, disallow, and sitemap.
- XML sitemapGenerate a urlset from one URL per line.
- Sitemap validatorCheck that the XML is well-formed and count loc tags.
- CanonicalGenerate the canonical link tag.
- Structured dataGenerate a simple JSON-LD block.
- FAQ schemaGenerate FAQPage from question | answer.
- Breadcrumb schemaGenerate a BreadcrumbList.
- HreflangGenerate alternate links.
- Redirect rulesGenerate an Nginx rewrite and an Apache Redirect.
- Links in HTMLExtract href and src and check the syntax. It does not request the addresses.
- Term densityCount the most repeated words.
- Snippet previewShow the title and description cutoff and the character counts.
- Favicon in HTMLFind link rel=icon in pasted HTML.
- HTML sizeMeasure bytes, tags, images, and scripts in the pasted text.