GIF Inspector Online — Free, No Upload Required
View GIF file metadata in your browser. Format version, dimensions, frame count, animation timing, color table details, and loop settings — parsed instantly without uploading.
Drop a file here
or click to browse · GIF files up to 50 MB
Paste from clipboard also works
How to Inspect a GIF File
- Drop a GIF file onto the tool above, or click to browse your files. You can also paste a GIF from your clipboard.
- The inspector reads the file header and extension blocks in your browser. No pixel data is decoded — only structural metadata is extracted, so results appear within milliseconds.
- Review the metadata table. It displays the format version, canvas dimensions, frame count, total animation duration, loop count, global color table details, file size, and any embedded comments.
Understanding GIF File Metadata
Every GIF file begins with a 6-byte header that identifies the format version (GIF87a or GIF89a), followed by a Logical Screen Descriptor that defines the canvas dimensions and global color table parameters. The inspector parses these structures along with all extension blocks to present a complete technical summary of the file.
Format Version
The GIF specification defines two versions. GIF87a, published in 1987 by CompuServe, supports static and animated images with a global color table of up to 256 colors. GIF89a, published in 1989, extended the format with Graphic Control Extensions (enabling per-frame transparency and animation timing), Comment Extensions (embedded text metadata), and Application Extensions (including the Netscape looping extension that enables infinite animation loops).
Nearly all animated GIF files in circulation use the GIF89a format. The version field is informational — both versions use the same LZW compression algorithm and color table structure. The primary practical difference is that GIF87a files cannot contain transparency or animation control data.
Canvas Dimensions
The Logical Screen Descriptor specifies the canvas width and height in pixels. These define the coordinate space for all frames in the animation. Individual frames can be smaller than the canvas and positioned at arbitrary offsets — a technique used in frame optimization to reduce file size by encoding only the pixels that change between frames.
Common GIF dimensions range from 240×240 for social media reactions to 640×480 for screen recordings. The GIF format supports dimensions up to 65,535 × 65,535 pixels, though files larger than 1920×1080 are rare due to the format's compression limitations.
Frame Count and Animation Duration
The frame count indicates the total number of image frames in the file. Static GIFs contain a single frame. Animated GIFs typically contain 10 to 500 frames, though the format imposes no hard limit. Each frame has an associated delay time specified in centiseconds (hundredths of a second). The total animation duration is the sum of all frame delays.
A frame delay of 0 or 1 centisecond is treated differently by different browsers. Most browsers enforce a minimum delay of 2 centiseconds (20 milliseconds) to prevent excessively fast playback. Some older browsers use a minimum of 10 centiseconds (100 milliseconds) for delays below 2 centiseconds.
Loop Count
The loop count is stored in a Netscape Application Extension block (application identifier "NETSCAPE2.0"). A loop count of 0 means the animation repeats indefinitely. A loop count of N means the animation plays N times and then stops on the last frame. If no Netscape extension is present, the animation plays once by default, though browser behavior varies.
Global Color Table
The global color table is a palette of RGB colors shared by all frames that do not define their own local color table. The table size is always a power of 2, ranging from 2 to 256 entries. Each entry is 3 bytes (one byte each for red, green, and blue channels), so a 256-color table occupies 768 bytes.
Frames can override the global table with a local color table, allowing different frames to use different palettes. This is useful for animations where the color content changes significantly between frames, but it increases file size because each local table adds 6 to 768 bytes per frame.
File Size
GIF file size depends on canvas dimensions, frame count, color complexity, and compression efficiency. A 100-frame 480p GIF with 256 colors typically ranges from 2 MB to 15 MB. The LZW compression algorithm built into the GIF format achieves better compression ratios when the pixel data contains more repetition — which occurs naturally with fewer colors and larger areas of uniform color.
Comments
GIF89a files can contain Comment Extension blocks with arbitrary text. These are commonly used to store attribution information, software identifiers (the application that created the GIF), copyright notices, or descriptive text. Comments are not displayed by image viewers — they are metadata only. This inspector extracts and displays all comment blocks found in the file.
GIF Format Technical Reference
The GIF (Graphics Interchange Format) specification was published by CompuServe in 1987 (GIF87a) and updated in 1989 (GIF89a). The format uses LZW (Lempel-Ziv-Welch) compression on indexed color data, supporting a maximum of 256 colors per frame from a 24-bit RGB color space. Despite its age and color limitations, GIF remains widely used for short animations due to universal browser support and the ability to loop without player controls.
When to Use GIF Inspector
The GIF inspector is useful for diagnosing animation issues (incorrect frame count, unexpected loop behavior), verifying file properties before uploading to platforms with size or dimension limits, understanding the color table structure before compression, and examining embedded comments or metadata. It provides the same information as command-line tools like gifsicle --info or identify -verbose, but runs entirely in your browser without installing software.
GIF Metadata vs Other Formats
Unlike JPEG (which stores EXIF data including camera settings, GPS coordinates, and timestamps) or PNG (which supports arbitrary text chunks), GIF metadata is limited to the format version, canvas dimensions, color table parameters, animation timing, and comment blocks. GIF files do not contain EXIF data, ICC color profiles, or XMP metadata. This makes GIF files inherently more privacy-friendly — they cannot inadvertently expose location data or device information.
Frequently Asked Questions
The inspector displays the GIF format version (87a or 89a), canvas dimensions (width and height in pixels), total frame count, animation duration in milliseconds, loop count (0 means infinite), global color table size, whether a global color table is present, embedded comments, and the file size in bytes.
GIF87a is the original 1987 specification supporting static and animated images with a global color table. GIF89a (1989) added transparency, animation control (frame delays, disposal methods), text overlays, and comment extensions. Nearly all modern GIF files use the GIF89a format.
The global color table is a shared palette of up to 256 RGB colors used by all frames in the GIF unless a frame defines its own local color table. The table size is always a power of 2 (2, 4, 8, 16, 32, 64, 128, or 256 entries). Smaller tables produce smaller files.
The loop count specifies how many times the animation repeats. A value of 0 means the animation loops indefinitely. A value of 1 means the animation plays once and stops. Most animated GIFs use a loop count of 0 for continuous playback.
No. The GIF file is read and parsed entirely in your browser using a Web Worker. No file data is transmitted to any server at any point. You can verify this by disconnecting from the internet — the tool continues to work.
This tool accepts GIF files up to 50 MB. Metadata extraction is lightweight — it reads the file header and extension blocks without decoding pixel data, so results appear within milliseconds regardless of file size or frame count.