Software Alternatives, Accelerators & Startups

Modify Header Value (HTTP Headers) VS RepDB

Compare Modify Header Value (HTTP Headers) VS RepDB and see what are their differences

Modify Header Value (HTTP Headers) logo Modify Header Value (HTTP Headers)

Modify Header Value (HTTP Headers) is a browser extension that allows you to add, modify or remove a header for any request to your preferred domains.

RepDB logo RepDB

Exercise dataset for fitness apps: transparent background, animations, no subscription
Visit Website
  • Modify Header Value (HTTP Headers) Landing page
    Landing page //
    2022-08-06
  • RepDB Standard exercise dataset
    Standard exercise dataset //
    2026-08-15
  • RepDB Starter tier
    Starter tier //
    2026-08-15

RepDB is a one-time-purchase exercise dataset for developers building fitness and workout apps โ€” not a subscription, not a rate-limited API. You download the data once and own it: JSON (and SQLite on the higher tier), WebP images, and full EN/DE/ES translations, with no per-request billing and no dependency on our servers staying up.

A free tier includes 250 exercises with flat-style 512ร—512 images, attribution-licensed for commercial in-app use. The Starter tier ($199) adds the full catalog in classic white-background style. Standard ($399) adds transparent 1024px images, looping animations, exercise relations (similar/progressions/regressions), workout templates, and embeddings โ€” exclusive to that tier.

Every exercise includes muscle-group highlighting, equipment/muscle icons, MET values, and safety/goal tags. Compared to GIF- or JPG-based competitor APIs, RepDB images are transparent WebP with no watermarks, so they drop into any app UI without a white box around them.

RepDB

Website
repdb.co
$ Details
freemium $299 / One-off
Platforms
Web Mobile
Release Date
2026 July

Modify Header Value (HTTP Headers) features and specs

  • Custom Header Management
    Allows users to add, modify, or remove HTTP headers, providing greater control over the information sent and received by the browser.
  • Testing and Debugging
    Facilitates the testing and debugging of web applications by enabling the manipulation of headers, which can simulate different server responses or client requests.
  • Security and Privacy
    Enhances security and privacy by allowing users to modify headers that might contain sensitive information or to block certain headers completely.
  • User-Agent Customization
    Enables the customization of the User-Agent string, allowing users to access content that might be restricted to certain devices or browsers.

Possible disadvantages of Modify Header Value (HTTP Headers)

  • Complexity for Non-technical Users
    May be difficult for non-technical users to understand and use effectively, as it requires knowledge of HTTP headers and their functions.
  • Potential for Misconfiguration
    Incorrectly modifying headers can lead to misconfiguration issues, which might break website functionality or cause security vulnerabilities.
  • Compatibility Issues
    Some websites might not operate correctly if certain headers are altered, leading to potential compatibility issues.
  • Performance Overhead
    Altering headers might introduce additional processing overhead, which can impact browser performance, especially if a large number of rules are defined.

RepDB features and specs

  • WebP Format Benefits
    start+peak exercise images
  • JSON
    relations, metadata, equipment
  • Transparency
    transparent background
  • Animations
    Animated loops in paid tier

Category Popularity

0-100% (relative to Modify Header Value (HTTP Headers) and RepDB)
Developer Tools
81 81%
19% 19
Datasets
0 0%
100% 100
Development
100 100%
0% 0
SEO Tools
100 100%
0% 0

Questions & Answers

As answered by people managing Modify Header Value (HTTP Headers) and RepDB.

What makes your product unique?

RepDB's answer:

RepDB is sold as a one-time download, not a metered API โ€” you own the JSON/SQLite data and WebP images outright, with no rate limits, no per-request billing, and no risk of the vendor cutting off access. It's also the only dataset in this space with EN/DE/ES translations, transparent (alpha-channel) images with no watermark, muscle-group highlighting, safety/goal tags, and looping animations on the higher tier.

What's the story behind your product?

RepDB's answer:

RepDB grew out of a consumer workout app its creator was building solo. Sourcing exercise images and data meant either paying for a subscription API with usage caps and no caching rights, or producing everything from scratch. The illustrated, multi-language dataset was built for us first, then split out as its own product once it became clear other indie developers had the same problem and preferred to buy the data outright rather than rent it through an API.

Why should a person choose your product over its competitors?

RepDB's answer:

Most alternatives are subscription APIs โ€” you pay monthly, you're capped on requests, and ExerciseDB's terms of use explicitly forbid caching or storing the data at all, so every image render is a live paid API call. RepDB is the opposite: pay once, download the files, self-host with zero ongoing dependency. It's also the only option offering true DE/ES localization and transparent images instead of a white box behind every exercise.

How would you describe the primary audience of your product?

RepDB's answer:

Solo developers and small teams building fitness or workout-tracking apps (iOS, Android, web) who need licensed exercise images and structured exercise data, but don't want to build their own media pipeline or depend on a rate-limited third-party API.

User comments

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Social recommendations and mentions

Based on our record, Modify Header Value (HTTP Headers) seems to be more popular. It has been mentiond 4 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.

Modify Header Value (HTTP Headers) mentions (4)

  • Reddit on desktop also died.
    Yep that started recently. I found a solution with the add-on Modify Header Value (HTTP Headers) , you need to add two rules:. Source: about 3 years ago
  • On PC, reddit started constantly showing me a banner to install the app when opening reddit-hosted images
    Going off of what a user said in the comments of another post complaining about this, you can get the old behaviour back by modifying the request headings. I've managed to do this using a Chrome extensions called Modify Header Value (HTTP Headers) (it's also available on Firefox, Opera, and Edge) and added a rule with the following parameters. Source: over 3 years ago
  • [Feature Request] User-Switcher for Android Firefox (Read post..)
    To change user agent on fenix (nighlty ,using custom collection )I use https://mybrowseraddon.com/modify-header-value.html It can also modify other header parameters . Source: over 4 years ago
  • Block mobile sites and elements and load normal full desktop sites instead?
    I ve had same problem as you if u use fenix u can solve it by using nightly and change userAgent in about:config (general.useragent.override) or install https://mybrowseraddon.com/modify-header-value.html (Modify Header Value (HTTP Headers) and change user agent per site basis. Source: over 4 years ago

RepDB mentions (0)

We have not tracked any mentions of RepDB yet. Tracking of RepDB recommendations started around Jul 2026.

What are some alternatives?

When comparing Modify Header Value (HTTP Headers) and RepDB, you can also consider the following products

Sky Live HTTP Headers - Sky Live HTTP Headers is an open-source browser extension that visually displays HTTP requests and response headers from every website you visit.

WebSniffer - WebSniffer is an online tool to outlook HTTP request and response headers.

HTTP-Repeater (HTTP/s Live Headers) (Beta) - HTTP-Repeater (HTTP/s Live Headers) (Beta) is a browser extension that lets you capture browser requests and repeat the process in a loop automatically.

HTTP Header Analyzer - HTTP Header Analyzer is an open-source browser extension that allows you to see and analyze the current HTTP request and response header from the website URL.

HTTP-TRACKER - HTTP-TRACKER is an advanced browser extension that allows you to examine HTTP request headers, cookies, response Headers, website data, cookies and modify request headers before sending them.

HTTP Header Spy - HTTP Header Spy is a browser extension that allows you to inspect the request and response header of any website URL.