MIME Type Lookup
Look up MIME types by file extension or find extensions for a MIME type. Covers 100+ common formats.
How it works
- 1Paste or type your text in the input field
- 2Click "Process" — processing happens in your browser
- 3Copy the result or download as a text file
What to do next
About MIME Type Lookup
MIME Type Lookup is a free, in-browser developer tool. Look up MIME types by file extension or find extensions for a MIME type. Covers 100+ common formats. The page exposes a small surface — input, controls, output — so a first-time visitor can complete the job without reading documentation.
MIME Type Lookup is shaped for the gap between "I'll do it by hand" and "I'll script it." When the job is small enough that automating it would take longer than doing it, but annoying enough to want a focused tool — that is the situation this page is built for.
MIME Type Lookup parses your file with standard browser APIs entirely inside the browser, applies the options you selected, and returns a download. The processing has no network step, which means a slow or intermittent connection does not slow down the work — once the page is loaded, only your CPU and RAM are involved.
Technically, the work is done by standard browser APIs, loaded as part of the page. Inputs are recognised automatically and validated before the engine begins processing. Files up to 0 MB are supported per run; that ceiling keeps browser memory usage stable on a wide range of devices.
The hard constraints are easy to remember. Maximum input: 0 MB. Multiple files per run: no — one input at a time, by design, to keep results predictable. The same controls apply on every run.
Anyone who works with developer utility on a casual basis — students learning new languages, backend developers inspecting requests, engineers debugging API payloads — finds MIME Type Lookup a quick way to get the result. The page loads in under a second, the controls are visible from a single screen, and the result downloads or copies in one click.
The output handed back by MIME Type Lookup is the output file. If you would prefer to keep the result in the browser instead of downloading it, you can copy it from the result panel and paste it directly into another tab — useful when the next tool in your workflow expects pasted text rather than a file.
For multi-step jobs, MIME Type Lookup sits next to Accept Header Parser, HTTP Header Analyzer, and API Response Formatter. None of them depend on each other — you can use MIME Type Lookup on its own — but together they cover the common variations of the task this page exists to handle.
MIME Type Lookup is honest about scope: it handles a single, well-defined developer utility step. Specialist edge-case work — uncommon formats, very large inputs, or pipelines that need scripting — is what dedicated desktop apps are for. This page handles the common case quickly.
A short note on how MIME Type Lookup came to look the way it does: every iteration started by watching how someone unfamiliar with the tool actually used it, then removing whatever got in their way. That is why the upload area dominates the screen, the run button is bigger than the secondary controls, and the result panel is unmissable when the job finishes.
If you also use a command-line tool for mime type lookup, MIME Type Lookup is a convenient alternative for the times you are on a different machine or helping someone who is not comfortable in a terminal. The output is a standard file in the format documented above.
Pro tip: MIME Type Lookup works just as well in a private/incognito window as in a normal one, which is occasionally useful when you want zero browser-history footprint of the job. Another tip: if the tool ever feels slow, it is almost always because the browser tab is competing for CPU with another tab — pausing or closing the heavy ones gives the engine room to work.
If the result is not what you expected, the most common causes are easy to check. Confirm the input is under the 0 MB ceiling — files just above the cap fail silently because the engine refuses to allocate the buffer. Confirm the input is one of the supported formats. And if the page itself feels slow, try closing other heavy tabs to free up memory; the engine runs in your browser, so it competes for the same resources as everything else open.
MIME Type Lookup is one of many single-purpose tools in the catalog. Each is built around the same single-page model. Use this one, close the tab, and come back the next time you need the same job done. None of the tools require prior knowledge of the others — each page is self-contained.
How it works
- 1Open the MIME Type Lookup workspace above. The interface is a single page, so there is nothing to navigate.
- 2Select the developer file you want to process — drag-and-drop and the file picker both work.
- 3Pick any non-default settings you need. Most users leave the defaults alone for the first run and only revisit if the result needs tuning.
- 4Hit the run button. standard browser APIs does the work in your browser tab.
- 5Download the result. The file is generated in your browser and saved through your normal download flow.
- 6Run additional jobs as needed. The same controls and defaults apply on every run.
Common use cases
- Inspect a regex against a test string before committing it using MIME Type Lookup.
- Compare two API responses to spot a regression.
- Generate a quick fixture without leaving the browser.
- Inspect a payload during local development without writing a script.
- Generate boilerplate from a single specification line.
- Pretty-print a minified blob during incident triage.
- Hash a string for a quick reproducibility check.
- Convert between data formats while wiring up an integration.
- Format a noisy log line into something a teammate can read.
- Validate a config blob before pushing to staging.
FAQ
What is a MIME type?
Multipurpose Internet Mail Extensions type — a standard identifier for file formats used in HTTP Content-Type headers (e.g. image/png).
Can I search by extension?
Yes — enter an extension like "jpg" or ".pdf" to find its MIME type.
Can I search by MIME type?
Yes — enter a MIME type like "application/json" to find associated file extensions.
How many formats?
Over 100 common formats including images, audio, video, documents, fonts, archives, and programming languages.
What about custom types?
Custom vendor types (application/vnd.*) may not be in the lookup table but are still valid MIME types.
Private?
Yes — lookup runs locally.
Is MIME Type Lookup mobile-friendly?
MIME Type Lookup runs in any modern mobile browser — Safari, Chrome, Firefox and the in-app browsers in most messaging apps all support the underlying APIs. Performance depends on the device: a recent phone handles typical inputs nearly as fast as a laptop, while older devices may take a few seconds longer near the 0 MB ceiling. The interface lays out cleanly on small screens, so you do not need to pinch-zoom to see the controls.
How do I run MIME Type Lookup over a folder of files?
MIME Type Lookup processes one input at a time by design — it keeps memory usage predictable on lower-end devices and makes results easier to verify. To handle a folder, run the tool once per file; the page stays loaded between runs and remembers your last-used settings, so the second run is essentially instant.
Can I self-host MIME Type Lookup for my team?
MIME Type Lookup is a static page running an open-source engine in your browser, so a typical corporate firewall does not get in the way as long as it allows JavaScript to load from Favtoo. For teams that need to host it themselves on an internal network, the underlying engine (standard browser APIs) is open-source and can be packaged into a private build with the same behaviour. Reach out via the Contact page if that is something you are exploring.
Is MIME Type Lookup keyboard accessible?
MIME Type Lookup uses native HTML controls wherever possible, which means keyboard navigation, focus rings, and screen-reader labels work the way the platform expects. The drop zone accepts files via the keyboard-accessible file picker as well as drag-and-drop, and result downloads use standard browser download flows. If you spot an accessibility gap, Favtoo treats it as a bug worth fixing.
How fast is MIME Type Lookup?
Most jobs finish in seconds. Speed scales with input size and with how many CPU cycles your browser tab has available — the engine runs in your browser, so it shares resources with whatever else you have open. For inputs near the 0 MB ceiling, expect anywhere from a few seconds to roughly a minute on a typical laptop. Closing other heavy tabs noticeably speeds things up.
Will I notice a difference in the output from MIME Type Lookup?
MIME Type Lookup is built to preserve quality wherever the underlying developer format allows it. Operations that are mathematically lossless (e.g. structural transformations, lossless re-encoding) round-trip with no perceptible change. Operations that involve a lossy codec inevitably introduce small artefacts at the byte level, but the defaults aim at the sweet spot where output looks or sounds the same to a normal viewer or listener while still being meaningfully smaller or faster than the input.
Does MIME Type Lookup ask for any browser permissions?
MIME Type Lookup only needs the standard web platform — file picker access for the inputs you choose to load, and optionally clipboard access if you copy the result rather than downloading it. There is no microphone, camera, geolocation or background-permission request, because none of those are needed for the work the tool does.
Can I call MIME Type Lookup from a script?
MIME Type Lookup is a browser-only tool by design and does not expose a hosted API. The reason is the same as the privacy story: there is no Favtoo backend doing the work, so there is no service to call. If you need to script the same transformation, the underlying engine (standard browser APIs) is open-source and can be used directly from your own code.
Which browsers are supported by MIME Type Lookup?
MIME Type Lookup works in any modern browser released in the last few years — Chrome, Edge, Firefox, Safari, Brave, Arc and the major Chromium derivatives are all supported. The underlying engine relies on widely-supported web APIs, so there is nothing exotic to install. If you are on a very old browser version and the tool fails to load, updating to the latest release of your preferred browser is the only fix needed.